Question

skin cells are lost daily even without injury. the cell cycle responds by promoting reproduction. repair. synthesis. growth.

Explanation:

When skin cells are lost daily without injury, the cell - cycle promotes reproduction to replace the lost cells. Repair is mainly for damaged cells due to injury, synthesis is part of the cell - cycle processes but not the main response here, and growth is more about an increase in cell size or overall organism size, not specifically about replacing lost cells.

Answer:

reproduction.