How do wetlands form?

Tributaries flow into rivers.
Runoff travels down the side of a divide.
Water builds up in a depression left by an ice sheet.
Groundwater comes to the surface and floods the land.

D) groundwater comes to the surface and floods the land

Explanation:

Groundwater like water from river or lake comes to a land and before it has a chance to go back into the soil or evaporate, more water comes and floods the areas, thus the previous water stays and new water stays as well. If this cycle is repeated, a wetland will form.

it is called the mitotic spindle