Annamacharya used the mudra “Venkateswara” in his compositions as a signature to denote devotion to Lord Venkateswara of Tirupati.
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Explanation of Other Options:
(A) Padmanabha: Mudra used by some other composers.
(B) Ramadasa: Mudra of Sant Ramadasa, a Marathi saint.
(D) Gopal Dasa: Mudra used by another composer.
Hence, the correct answer is option (C).