CDS

B.A will be a better option if you want to make your career by clearing CDS exam. But for INA and Air force Academy you must have a degree in Engineering.
For INA: The aspirants must have a degree in Engineering. For Air Force Academy: The aspirants should have passed 12th standard with Physics and Mathematics and having a degree from a recognised university or Bachelors degree in engineering / technology. As we Know Why all prefer B.A. For CDS preparation because there are three different exams are organised by UPSC.
EXAM-I Elementary mathematics
EXAM-II English
EXAM-III General studies
So, if you go for B.A. for your graduation, you will have an advantage of preparing for third exam in parallel with your graduation. But you should choose subjects wisely as per exam syllabus because if your sociology and all this will not be beneficial as per your target. Believe me GK of CDS is quite tough. Questions are also asked about world. Most importantly, you have to gain at least 20% in each exam so that your OMR sheets go for checking. H

If you want to have a long-term career in the army, then IMA is a better choice, whereas if you just want to live in the army for a few years, then OTA is better.
1. The basic difference between IMA and OTA is that the Indian Military Academy is for permanent commissioned officers who will serve up to 30 years, whereas the Officer Training Academy, Chennai, is for short-service commissioned officers who can serve up to 14 years maximum in the army. Hence, you will have the option of leaving the army after your compulsory service of ten years as an SSC officer in OTA.
2. Also, those who don't like mathematics can skip the compulsory math paper and opt for OTA. To join IMA, you need to score higher in the CDS exam.
3. OTA also has cadets of both genders, whereas IMA only has male cadets. Both academies are reputed in the country and were established for different purposes. You can either opt for OTA or IMA if you have allocated both. Most of the male army aspirants usually go for IMA, whereas for girls, only the OTA option is there.

No, there is no strong data available that all short-service officers (OTA) do corporate jobs after serving for 10 years in the army. This is for multiple reasons:
1. Some officers prefer to extend their service tenure for four more years, as per army rules.
2. Around 5 percent get a permanent commission, depending on the vacancy.
3. Some other officers prefer to go for other government jobs, such as railways, as there are relaxations and quotas for ex-servicemen in many government jobs.
4. Some prefer to do higher studies, such as an MBA or Ph.D. before starting a new career.
5. Some other SSC officers choose to guide defense aspirants to achieve their goals. Therefore, not all SSC officers choose to take this path to start a new career after retirement.

The General Knowledge (GS) paper of CDS is a bit tricky due to the vast syllabus. This strategy may help you sail through the GS paper of CDS:
1. Since the syllabus is vast therefore you need to analyze the previous year's papers to understand the pattern of repeating topics.
2. You must select the most frequently occurring themes and properly prepare them. For other topics, you may simply have an idea about the topic.
3. You do need to study or solve each and every question as there is a negative marking. Simply mark those questions about which you are sure.
4. Read current affairs-related subjects well, such as polity and security, as it will help you in SSB also.
5. Similarly, a strong foundation in Science and geography is also necessary to score well in the GS paper. You can be a little selective in the history section.
6. Do not ignore current events and allow adequate time to revise this section.
7. Practice as much as possible to improve your accuracy in the GS Paper. Best Wishes.

There is no attempt limit in the Combined Defence Services CDS exam. This exam is conducted twice a year, and you can appear any number of times after attaining the age of 19. However, there is an age limit in CDS which is as follows:
1. For the Indian Naval Academy, the maximum age limit is 22 years, up to which you can apply.
2. To apply to the Air Force Academy, the upper age limit is 23 years.
3. The maximum age at which you can apply for the Indian Military Academy (IMA) is 24.
4. If you want to apply for the Officers' Training Academy, the maximum age is 25 years. Therefore, you can apply for the CDS exam until you attain the maximum age of 25 years.

The syllabus is according to the exam pattern of the CDS written exam. The exam pattern is as follows: (a) For the Indian Military Academy, Indian Naval Academy, and Air Force Academy, there are 3 subjects each of 100 marks and 2 hours duration. These subjects are English general knowledge, and elementary mathematics. (b) For the Officers' Training Academy, the elementary mathematics subject is not asked. The syllabus for these subjects is as follows:
1. English (Code 01): The question paper will test your understanding of English and workmanlike use of words. Subtopics which are usually asked includes Basic grammar, Idiom and phrases, synonyms and antonyms etc.
2. General Knowledge (Code 02): Current events and question on basic general awareness such as on Physics Chemistry Biology Economics, polity, history of India and geography etc.
3. Elementary Mathematics (Code 03): This includes subtopics of arithmetic, the Number System and elementary number theory. Algebra Trigonometry geometry, Mensuration and Statistics are also asked.

The Union Public Service Commission UPSC administers the Combined Defence Services CDS exam. I assume you want to compare the Civil Service and CDS. Both are reputed government jobs but are unique in the nature of work. Here is a brief comparison given between the two services:
Civil Services:
1. It includes services such as IAS IPS, and IFS. These are responsible for policy making and implementation.
2. Civil servants maintain public law and order. These services are comparatively less adventurous than CDS.
3. It is mostly a non-uniformed service except for IPS and IRS (C&CE).
4. Civil servants mostly deal with civilians and therefore live close to civilian areas.
5. Civil servants do not have perks such as a canteen, but their salary is usually on par with other group A services. CDS:
1. The CDS exam is generally conducted for defence roles in the Indian Army, Airforce, and Navy.
2. It deals with Indian security and therefore is more adventurous. It can directly expose you to the frontline.
3. The CDS is a well-known uniformed service.
4. CDS does not involve much civilian exposure and officers mostly stay in cantonment areas.
5. CDS officers have additional perks, like canteen service. Therefore, both services are good, and it depends on your aptitude to choose which one you want to choose. If you want an adventurous life that directly involves protecting the country, join the CDS. But if you want to work in the service of people, join the civil service, such as the IAS.