When a Student Performs an Endothermic Reaction in a Calorimeter

When a student performs an endothermic reaction in a calorimeter, how (if any) does the calculated value of ΔH differ from the actual value if the heat exchanged with the calorimeter is not taken into account?

A) ΔH_calc is less positive because the reaction absorbs heat from the calorimeter.
B) ΔH_calc equals the actual value because the calorimeter does not absorb heat.
C) ΔH_calc is more negative because the calorimeter always absorbs heat from the reaction.
D) ΔH_calc is less negative because the calorimeter absorbs heat from the reaction.
E) ΔH_calc is more positive because the reaction absorbs heat from the calorimeter.