Answer:
D. Renal autoregulation.
Step-by-step explanation:
It is a mechanism that is responsible for maintenance of relatively constant renal blood flow and GFR i.e glomerular filtration rate. It is the ability of the blood vessels to resist stretching during increased arterial pressure, a mechanism called myogenic mechanism. Whenever there is increase in blood pressure, the walls of arteriole tend to stretch. The wall of afferent arteriole in the glomerulus however responds to the stretch by contraction i.e. the diameter is reduced. This increases the resistance to flow, thereby reducing the GFR and renal flow during high BP.