Carbon dioxide, oxygen, water, and acids may all cause chemical weathering. Mechanical weathering is the process of breaking a large rock into smaller pieces without changing the minerals in the rock. Mechanical weathering may be caused by frost, ice, plant roots, running water, or heat from the sun.
Your answer would be D. The possible combinations of alleles in offspring based on the parents genetic makeup. The punnet square is basically used to determine what the outcome of an offspring would be.