Which equation is the CORRECT representation of the process shown below?

A

$$Q_{A1-2} + W_{A1-2} = Q_{B2-1} + W_{B2-1}$$

B

$$Q_{A1-2} - W_{A1-2} = Q_{B2-1} - W_{B2-1}$$

C

$$Q_{A1-2} + Q_{B2-1} = W_{A1-2} + W_{B2-1}$$

D

$$Q_{B2-1} - Q_{A1-2} = W_{B2-1} - W_{A1-2}$$