Out of the 200 million ejaculated sperm, only about _________ reach the vicinity of the egg.

A. Renal corpuscle: Blood plasma is filtered in the renal corpuscle, which includes the glomerulus and Bowman's capsule.

B. Renal capsule: The renal capsule is the outer protective layer of the kidney and does not filter blood plasma.

C. Renal tubule: The renal tubule is involved in reabsorption and secretion, not in the initial filtration of blood plasma.

D. Renal column: The renal column is a structural part of the kidney, not involved in filtering blood plasma.

A. Diuretics increase urine output by inhibiting the reabsorption of water and sodium in the kidneys, which leads to increased water loss. This action is opposite to water conservation, making this the correct answer.

B. The counter current exchange system in the kidneys helps conserve water by maintaining a high osmolarity in the medulla, which facilitates the reabsorption of water in the collecting ducts. This system contributes to water conservation.

C. The collecting duct plays a crucial role in water reabsorption. Antidiuretic hormone (ADH) increases the permeability of the collecting duct to water, allowing more water to be reabsorbed back into the bloodstream, contributing to water conservation.

D. The counter current multiplier is a mechanism in the loop of Henle that creates a concentration gradient in the kidney medulla, which is essential for water reabsorption in the collecting ducts. It contributes to water conservation.