Pigment is the
a. ground up solids that contain color.
b. surface a painting is created on.
c. mixture of hue and water.
d. liquid substance used in paint and other media to bind particles of pigment together.

Pigment is A) ground up solids that contain color. 

This would be the most correct answer. We often find pigment in solid form in nature or create it artificially ourselves. In art classes, some schools still prefer that children color their paintings etc. with pigment which is moistened with water and is then used as a base for coloring, while others used liquid colored tubes :)