O an increase in insect populations that live mainly in
soil and grasses.
O
the contamination of local watersheds from runoff
of toxins and fertilizers.
O
sediment buildup in areas of sitting water.

Humans can affect weathering and erosion in several ways.  humans cause  increases in acid rain and pollution, which increase the amount of  weathering  agents in the air and water, and then on land.for an easy answer: 1) acid rain2) pollution

C. a mature ovule of a plant.

According to edgenuity, the answer is c.