Density is A) the amount of mass in an object
B) the amount of mass in a given amount of space
C) the amount of space an object takes up
D) the weight of an object

b

Explanation:

Density is a measure of mass per volume. The average density of an object equals its total mass divided by its total volume. An object made from a comparatively dense material (such as iron) will have less volume than an object of equal mass made from some less dense substance (such as water).