Question

1. which statement is true of all matter?

a. it has mass
b. it can be seen
c. it exists only as a solid
d. it maintains its shape and size

Explanation:

Matter is defined as anything that has mass and takes up space. Some matter is invisible (e.g., gases like oxygen), matter can exist in states other than solid (liquid, gas, plasma), and only solids maintain a definite shape and size (liquids and gases do not). So the only statement true for all matter is that it has mass.

Answer:

A. It has mass