Arrows in the Energy Diagram Below Represent Enthalpy Changes Occurring

Multiple Choice

Arrows in the energy diagram below represent enthalpy changes occurring in the exothermic formation of a solution:
ΔH_soln = enthalpy of solution
ΔHsolute-solute = enthalpy change involving solute-solute interactions
ΔHsolute-solvent = enthalpy change involving solute-solvent interactions
ΔHsolvent-solvent = enthalpy change involving solvent-solvent interactions
-Which arrows represent ΔH_{solute-solute} and ΔH_{solvent-solvent}?

A) arrow (a) and arrow (b)
B) arrow (a) and arrow (c)
C) arrow (a) and arrow (d)
D) arrow (c) and arrow (d)