Neelam Sanjiva Reddy is the only President of India who had been Speaker of the Lok Sabha — option 3.

His career. He was Chief Minister of Andhra Pradesh, then President of the Indian National Congress, then Speaker of the Lok Sabha — twice, in 1967-69 and again in 1977 — and finally President of India from 1977 to 1982. Two further distinctions attach to him: he resigned his party membership on becoming Speaker in 1967, setting a precedent for the impartiality of the office; and he was elected President unopposed in 1977, the only person to be so elected. He had also stood for the presidency in 1969 and lost — to V. V. Giri.

Why the office of Speaker matters here. The Speaker presides over the Lok Sabha, decides whether a bill is a Money Bill under Article 110, exercises a casting vote, and rules on disqualification for defection under the Tenth Schedule. Election to the presidency from that office is unusual, since the Speaker is expected to be non-partisan and the presidency is filled by an electoral college of MPs and MLAs voting by proportional representation with a single transferable vote, under Article 55.

A useful cross-fact is that Giri and Reddy were the two rivals of the celebrated 1969 contest, in which the Congress split over the party’s official candidate — so both names in this question belong to the same episode, eight years before Reddy finally reached the office.

Hence, the answer is Neelam Sanjeeva Reddy.