In a lab, calcium chloride is dissolved in water in a test tube. As it dissolves the test tube gets warmer. Which of these is a good explanation for this?

A.) This is an endothermic reaction
B.) As the solute dissolves it gives off heat to the surrounds.
C.) As the solute dissolves it takes heat from the surrounds
D.A contaminant must have been present in the water as mixing never creates heat.