OA is D. But why is it in Simple past. Shouldn't this be in Present perfect?
In October, the chairman of Tata Sons, Ratan Tata, gifted $50 million to his alma mater, the Harvard Business School, in an attempt to give back to the school a little bit of what it had given him.
This is the correct answer Choice D which uses the simple past tense. This usage is correct here because the sentence is stating general fact about Ratan Tata that he gifted some money to his alma mater. We use past perfect tense when there are two past events. Past perfect is used for the event that took place earlier.
However, in this sentence, we getting general information about what Ratan Tata did. All the general facts must be written in simple tense (past/present/future depending upon the context of the sentence).
Also notice the use of past perfect tense “had given” towards the end of the sentence. This verb is written in the past perfect tense because Harvard had given, say the knowledge or education to Tata, way before October when Tata gifted the money. If we write both the verbs in the past perfect tense then this suggested time gap between the two verbs will become obscure.
'A' seems good but a little bit awkward. Maybe somebody can explain better why we eliminate 'A' .
Choice A: In October, the chairman of Tata Sons, Ratan Tata, gifted $50 million for his alma mater, the Harvard Business School to give back to the school a little bit of what it:
This sentence uses the wrong idiom “gifted for”. The correct idiom is “gifted to”. The incorrect idiom makes the sentence incorrect. Also, in the correct choice, the phrase "in attempt to" clarifies the purpose of the gift furthermore. This is missing in Choice A. The to + verb (to give back) is denoting the purpose of the gift but the additional phrase certainly enhances the meaning of the sentence.
Hope this helps.