Biology

The correct answer is that D.cholesterol allows for flexibility in the membrane to expand and contract.

Cholesterol is interspersed among the phospholipids in the cell membrane. At high temperatures, it acts to reduce the fluidity of the membrane. It restricts the movement of the phospholipid molecules, preventing the membrane from becoming too fluid and losing its integrity.

At low temperatures, cholesterol helps maintain the fluidity of the membrane. It prevents the phospholipids from packing too closely together and forming a rigid s...