The correct answer is:
A. Groundwater flows through the spaces in soil and rock, affected by gravity and pressure.
Groundwater movement is primarily influenced by factors such as the gradient of the water table, the permeability and porosity of the sediment or rock, and the presence of confined or unconfined aquifers. Gravity plays a significant role as it pulls the water downward, while pressure differences within the aquifer can also drive the flow of groundwater.