How Does the Hypothalamus of the Sexually Mature Human Male

How does the hypothalamus of the sexually mature human male regulate reproductive hormone levels?

A) The hypothalamus continuously secretes large amounts of GnRH.
B) The hypothalamus responds to low levels of testosterone by synthesizing and releasing testosterone.
C) The hypothalamus secretes GnRH in brief pulses every two to three hours.
D) The hypothalamus secretes LH in response to high levels of testosterone.
E) The hypothalamus responds to low levels of GnRH by synthesizing and releasing testosterone.