A sample of a substance has a high density, yet a low particle motion. This sample must be a

A) gas.

B) liquid.

C) plasma.

D) solid.

The most possible answer is letter B) Liquid.

If we are going to base the answer to the motion of particles, liquid is the best answer since solid's particle cannot move for they are tightly packed while the particles of gas and plasma (ionized gas) are free and move at high speeds.