Only 10 percent of contemporary U.S. adults will make a marriage-like commitment

Prenatally, development happens in a "head to tail" pattern known as:

proximodistal. cephalocaudal. neurogenesis. synaptogenesis.

The trichromatic theory states that:

A) the visual system treats triads of color as antagonistic to each other. B) three types of color feature detectors in the visual cortex are responsible for color perception. C) three types of cones exist, each sensitive to a certain range of wavelengths. D) species that detect ultraviolet light perceive three colors that are outside of the range of humans.