$C_4$ plants are found among

What is the primary $CO_2$ acceptor in $C_4$ plants?

Identify $A, B, C$ and $D$ in the given figure and choose the correct option accordingly.

The enzyme which catalyzes the primary carboxylation step in the photosynthetic $C_4$ cycle is:

The $C_{4}$ plants are twice as efficient as $C_{3}$ plants in terms of fixing $CO_{2}$ but lose only $........$ as much water as $C_{3}$ plants for the same amount of $CO_{2}$ fixed.

Provide the full names for the following abbreviations:
$(1)$ $PEP$
$(2)$ $PEPcase$