Which organelle is the center of the cell that controls its activities?

• A. Centrosome
• B. Nucleus
• C. Cytoplasm
• D. Cell membrane

Answer: (B)

Understanding which organelle acts as the cell's control center by housing genetic material and directing activities. The nucleus is where the cell keeps its DNA and regulates gene expression, guiding which proteins are made and how the cell responds to signals. This control over protein production and response patterns makes the nucleus the command center of cellular operations. The centrosome's role is to organize microtubules during cell division, not to regulate overall activities. The cytoplasm is the gel-like area where metabolic processes happen and where organelles reside, but it doesn't govern the cell's activities. The cell membrane controls what enters and leaves and facilitates communication with the environment, but it does not direct cellular functions from within.