which word describes the amount of matter an object contains?\n○ altitude\n○ density\n○ mass\n○ pressure

Brief Explanations:

To solve this, we analyze each option:

• "altitude" refers to height above a reference point, not matter amount.
• "density" is mass per unit volume, not total matter.
• "pressure" is force per area, unrelated to matter amount.
• "mass" is defined as the amount of matter in an object.

Answer:

B. mass