In a paper that I have been reading (https://cs.nyu.edu/~ganesh/zk.pdf), in one of the proofs, this has been said:
The simulator works as follows: It uses the OT simulator to extract the prover’s input $x_0$ to the OT.
How exactly does this work? There's nothing defined in the paper itself, and I couldn't find anything related to an extractor for an oblivious transfer protocol. (The paper also uses extractors for ZKPOK, but that has been defined)