Question

How do freeze-thaw cycles cause weathering?

A. When water moves into a crack and freezes, it expands and forces the crack wider.
B. When water freezes to ice on a rock, it absorbs some of the rock particles into its ice structure.
C. Each time ice melts on a rock, it washes away a small amount of the rock's outer layer.
D. The expansion and contraction of the rock due to the changes in heat cause it to begin breaking apart.

Answer 1

A. When water moves into a crack and freezes, it expands and forces the crack wider.

Step-by-step explanation:

A crack in a rock can fill with water which then freezes as the temperature drops. As the ice expands, it pushes the crack apart, making the crack larger. When the temperature rises again, the ice melts, and the water fills the newer parts of the crack. Once the water freezes again when the temperature drops, the expansion of the ice causes further expansion to the crack.