Question

In which of the following organism, testes descends into scrotum in breeding season but in non-breeding season goes up?

• A. Frog
• B. Kangaroo
• C. Shrew
• D. Bat

Answer 1

The correct option is D Bat

In all mammals, the testes descend into the scrotum, which is outside the body cavity. Scrotum maintains the temperature 1-3 ${}^0$C lower than the body temperature which is necessary for sperm production. In bats, the testes descend only during the mating or breeding season for sperm production but in the nonbreeding season it goes up as there is no requirement of sperm.
Therefore, the correct answer is option D.