The question is incomplete and the complete question is attached.
Answer:
Testes
Explanation:
In the given question, the male reproductive structure has been provided and in this male reproductive structure, only "Testes " which occurs in the pairs are known to form the male gametes.
The male gametes called sperms are formed from the spermatocytes which by the process of meiosis produces four spermatozoa which later mature into the spermatids and sperms.
Thus, Testes is correct.
