The correct answer is option 1 - Khrushchev. In December 1962, Soviet leader Nikita Khrushchev declared that China was responsible for the Sino-Indian War of 1962. This war took place between China and India and resulted in a victory for China. It was a brief but intense conflict over a disputed border region in the Himalayas.

It is important to understand that Khrushchev was the leader of the Soviet Union at the time and had a significant influence over Soviet foreign policy. His declaration blaming China for the war reflected the strained relationship between the two communist countries during that period.

Option 2 - Bulganin was a Soviet leader, but there is no record of him declaring China responsible for the Sino-Indian War of 1962.

Option 3 - Suslov was a Soviet politician, but there is no record of him declaring China responsible for the war.

Option 4 - Malenkov was also a Soviet leader, but there is no record of him making such a declaration.

Overall, it was Khrushchev who made the declaration, emphasizing the tense relations between the Soviet Union and China during that time.