In the pulley system shown the movable pulleys $A$,$B$ and $C$ have mass $m$ each, $D$ and $E$ are fixed pulleys. The strings are vertical, light and inextensible. Then, 

pulleys $A$,$B$ and $C$ all have acceleration $\frac{g}{3}$ in downward direction

pulley $A$ has acceleration $\frac{g}{3}$ in downward direction and pulleys $B$ and $C$ have acceleration $\frac{g}{3}$ each in upward direction.

pulleys $A$ and $B$ have acceleration $\frac{g}{3}$ each in downward direction and pulley $C$ has acceleration $\frac{g}{3}$ in upward direction

the tension throughout the string is the same and equals $T=\frac{2mg}{3}$