Energy is released during which phase changes

I think the phase changes that involves the release of energy is  change from Liquid to solid and also change from gas to liquid. The latent heat of fusion involves energy flow during the change of phase from solid to liquid. This change is endothermic, which means the system absorbs energy on going from solid to liquid, however when the direction is from liquid to solid the change would be exothermic. The same happens when we talk about latent heat of vaporization where change of phase from liquid to gas is endothermic, and the change form gas to liquid is exothermic.

The answer is probably c. xylem