Annamacharya employed the mudra “Venkateswara” in his compositions as a signature, signifying his devotion to Lord Venkateswara of Tirupati.
Explanation of Other Options:
(A) Padmanabha: A mudra utilized by different composers.
(B) Ramadasa: The mudra of Sant Ramadasa, a Marathi saint.
(D) Gopal Dasa: A mudra associated with another composer.
Therefore, the correct option is (C).