The nucleus includes all of the following structures except
a. cytoplasm.
b. nucleolus.
c. chromatin.
d. dna.

Option A, Cytoplasm

Explanation:

Cytoplasm is the fluid contained with in the cell membrane into which all cell organelles are found including the nucleus. Cytoplasm basically has two parts a) endoplasm and b) ectoplasm. The endoplasm has all the organelles while the ectoplasm is the fluid at the periphery of cell membrane. The cell memebrane keep the cytoplasm confined  with in the cell and does not allow it to spill.

Since all the cell components are found with in the cytoplasm, it is clear that cytoplasm lies out of the nucleus. Thus, option A is correct.

voluntary muscles are controlled by the cerebellum.