Three beakers labelled as A, B and C each containing 25 mL of water were taken. A small amount 
of NaOH, anhydrous ${\mathrm{CuSO}}_4$ and NaCl were added to the beakers A,B and C respectively. It was
observed that there was an increase in the temperature of the solutions contained in beakers A and 
B, where as in case of beaker C, the temperature of the solution falls. Which one of the following 
statement (s) is (are) correct
i) In beakers A and B exothermic process has occurred 
ii) In beakers A and B, endothermic process has occurred
iii) In beaker C exothermic process has occurred
iv) In beaker C endothermic process has occurred