Based on the options provided and the context of heat being removed from a substance, the correct answer would be:
B. it to form a solid as its particles move farther apart.
When heat is removed from a substance, the particles lose energy and move closer together, typically forming a solid from a liquid (freezing). However, it's important to note that this choice does not accurately reflect the behavior of particles in their states of matter since they generally move closer together rather than farther apart when transitioning to a solid.
The more correct phrasing for the change should reflect that removing heat causes the particles to move closer together to form a solid, but since that is not an option, the best fit is option B with the understanding that particles move closer rather than farther apart.
So, if we consider the states of matter correctly, heat removal usually leads to solidification (freezing) where particles indeed come closer together. Therefore, you might actually look for a choice that indicates this behavior.