The correct option is A Pancreas
A mixed gland is one which acts as both an enodcrine and an exocrine gland. The pancreas is a mixed gland. Its exocrine part secretes enzymes like trypsinogen. Its endocrine part secretes hormones like insulin and glucagon.
Testes and ovaries are organs with dual roles. The are both gonads and endocrine glands. Testes produce sperms and their endocrine part secretes the hormone testosterone.
The ovary produces ova, and its endocrine part secretes hormones like estrogen and progesterone.