Match List I with List II : List I List II A. Vocal sacs I. Present on the first digit of forelimbs in males B. Copulatory pad II. Helps in swimming in both sexes C. Webbed digits III. Receives sound signals in both sexes D. Tympanum IV. Present only in males for sound production Choose the correct answer from the options given below :

Step-by-step solution

Male frogs can be distinguished from female frogs by the presence of sound producing vocal sacs (A matches with IV) and a copulatory pad on the first digit of the forelimbs (B matches with I). These structures are absent in female frogs. Webbed digits are present in both sexes and help in swimming (C matches with II). The tympanum is present in both sexes and represents the ear, which receives sound signals (D matches with III). Therefore, the correct matching is A-IV, B-I, C-II, D-III. Answer: A-IV, B-I, C-II, D-I