Which of the following controls could be used if the voice pitch of a single-sideband signal returning to your CQ call seems too high or low?

Explication

An SSB signal recovers voice by mixing against the receiver's local oscillator, so a small tuning offset shifts every recovered audio frequency and the voice sounds too high or too low. Receiver incremental tuning, also called the clarifier, moves only the receive frequency to correct that without disturbing the transmit frequency.