How might heating the molecules inside the bottle change the motion of the molecules?

Heat causes the molecules to move faster, (heat energy is converted to kinetic energy ) which means that the volume of a gas increases more than the volume of a solid or liquid. However, gases that are contained in a fixed volume cannot expand - and so increases in temperature result in increases in pressure.

Ithink it is letter b, i may be wrong but i think that is the answer

Because they're in different places for this the temperature varies.