Question: Which Soviet mathematician was interrogated by the KGB as a result of his or her work, Sergei Novikov or Bella Subbotovskaya?
Sentence (from "Sergei Novikov (mathematician)"): Sergei Petrovich Novikov (also Serguei) (Russian: Серге́й Петро́вич Но́виков) (born 20 March 1938) is a Soviet and Russian mathematician, noted for work in both algebraic topology and soliton theory.
Relevant evidence: Yes