Parliament can Amend the provision on official language of India under the Constitution by

1. A

   a simple majority of its members

   Many official-language provisions in Part XVII can be given effect or altered by ordinary legislation, which in Parliament means a simple majority of members present and voting, subject to quorum. The Commission keys a simple majority of its members. This option is the official key.

2. B

   2/3rd majority

   A two-thirds majority is the special-majority track under Article 368 for many constitutional amendments, not the route the paper assigns to official-language provisions. This option is not the key.

3. C

   3/4th majority

   A three-fourths majority is not a standard amending figure in the Constitution of India. This option is therefore wrong.

4. D

   support of 1/3 of its members

   Support of one-third of members would not pass an ordinary Bill or an amendment. This option is not the key.

Summary. Official key is (a) a simple majority of its members. Part XVII language clauses are treated in standard Indian polity teaching as amendable or operable by ordinary majority, unlike entrenched federal provisions that need special majority and State ratification. Two-thirds, three-fourths and one-third do not match that teaching as keyed. Only (a) is the stored answer.