After ovulation, the oocyte:
a. waits passively for a sperm to penetrate.
b. releases negative ions that create an electrical gradient that all sperm swim toward.
c. releases chemotaxic signals to attract sperm to its location.
d. propels itself toward seminal fluid by calcium-dependent kinesis.

C. releases chemotaxic signals to attract sperm to its location.

Explanation:

An oocyte  is female gametocyte which is involved in the reproduction. It  is produced in ovary during the female gametogenesis. After ovulation, during luteal phase, egg is available to be fertilized by the sperm.

Sperm are attracted toward the eggs by the process of chemotaxis which is  by following the gradient of chemical secreted by egg.

Thus, the oocytes in the female body control not only type of sperm they want ot attract, but also time at which they attract them.

a. by using fur or clothes to trap heat energy near the body