In which year full diplomatic relations were restored between India and China?

1976

The correct answer is Option (4) → 1976

It took more than a decade for India and China to resume normal relations. It was in 1976 that full diplomatic relations were restored between the two countries. Atal Behari Vajpayee was the first top level leader (he was then External Affairs Minister) to visit China in 1979. Later, Rajiv Gandhi became the first Prime Minister after Nehru to visit China. Since then, the emphasis is more on trade relations between the two countries.