Question

what is the main function of the nucleus in an animal cell?
to sort and package proteins and other substances
to send instructions to different parts of the cell
to make proteins
to store waste in the cell

Explanation:

The nucleus in an animal cell contains the cell's genetic material (DNA) and is responsible for controlling cell activities by sending instructions (in the form of RNA) to different parts of the cell. "To sort and package proteins..." is the function of the Golgi apparatus, "to make proteins" is for ribosomes, and "to store waste..." is for vacuoles. So the correct function of the nucleus is to send instructions to different parts of the cell.

Answer:

to send instructions to different parts of the cell