The hypothalamus (A) synthesizes all of the hormones produced by the pituitary gland. (B) influences the function of only one lobe of the pituitary gland. (C) produces only inhibitory hormones. (D) regulates both reproduction and body temperature.

Option D, regulates both reproduction and body temperature

Explanation:

Hypothalamus regulates the internal stability of the body by maintaining homeostasis. It is a small part of the brain that acts as a command center for most of the body functions. Along with this, it also co-ordinates the autonomic nervous system. Just like a thermostat, hypothalamus maintains the body temperature. It also regulates and controls the stimuli and associated responses both internally and externally. Therefore, it is also responsible for regulating the sexual feelings and hence the reproduction

Thus, option D is correct