Match List-I with List-II.

	List-I		List-II
A.	Heart	I.	Erythropoietin
B.	Kidney	II.	Aldosterone
C.	Gastro-intestinal tract	III.	Atrial natriuretic factor
D.	Adrenal Cortex	IV.	Secretin

Choose the correct answer from the options given below :

To match each organ in List‑I with the hormone it primarily produces, we consider the well‑known physiological functions of these organs.

Heart (A) releases the hormone that regulates blood volume and pressure by promoting sodium excretion and vasodilation. This hormone is the atrial natriuretic factor (ANF), which is listed as item III in List‑II.

Kidney (B) is the main site of production for the hormone that stimulates red blood cell formation in response to low oxygen levels. That hormone is erythropoietin, shown as item I.

Gastro‑intestinal tract (C) secretes a peptide that stimulates the pancreas to release bicarbonate‑rich fluid, aiding digestion of acidic chyme. This peptide is secretin, corresponding to item IV.

Adrenal cortex (D) synthesizes a mineralocorticoid that controls sodium and potassium balance, thereby regulating blood pressure. This hormone is aldosterone, which appears as item II.

Putting these matches together gives the final pairing:

A → III, B → I, C → IV, D → II.