What structure does the membranous system form in the chloroplast?

Which of the following statements are correct?
$(A)$ The number of chloroplasts varies from $1$ per cell in $Chlamydomonas$, a green alga, to $20-40$ per cell in the mesophyll.
$(B)$ Out of the two membranes of chloroplasts and mitochondria, the inner membrane is relatively less permeable.
$(C)$ Thylakoids are arranged in stacks like the piles of coins called grana (singular: granum) or the intergranal thylakoids.
$(D)$ The stroma of the chloroplast contains enzymes required for the synthesis of carbohydrates and proteins.

Which plastid is responsible for the process of photosynthesis?

Which of the following is correctly represented as a cellular organelle and its function?

Many cells function properly and divide mitotically even though they do not have

The $DNA$ present in chloroplast is: