Assertion: The testes are situated outside the abdominal cavity within the scrotum.
Reason:: Scrotum helps to maintain low temperature of testes, necessary for spermatogenesis.

Both Assertion (A) and Reason (R) are correct and R is the correct explanation of A.

The testes are situated outside the abdominal cavity within a pouch called scrotum. The scrotum helps in maintaining low temperature of the testes (2-2.5 degree C lower than the normal internal body temperature ).