Which organelle is a protein network in the cytoplasm that provides structural support?

• A. Lysosomes
• B. Cytoskeleton
• C. Ribosomes
• D. Mitochondria

Answer: (B)

Proteins form a filamentous network in the cytoplasm that gives the cell its shape, provides mechanical support, and helps organize and move cellular components. This network is the cytoskeleton, made up of actin filaments, intermediate filaments, and microtubules, each contributing to strength, structure, and transport. Lysosomes digest waste materials, ribosomes synthesize proteins, and mitochondria generate ATP for energy. Because the description calls out a protein framework inside the cytoplasm that maintains structure, the cytoskeleton is the best fit.