Which of the following statements is incor- rect

Options

A. ADH- prevents conversion of angio-tensinogen in blood to angiotensin
B. Aidosterone -facilitates water reabsorp- tion
C. ANF- enhances sodium reabsorption
D. Renin - causes vasodilation

Explanation

To determine which statement is incorrect, let's analyze each of the statements provided in the question regarding the roles of different hormones and factors involved in excretion and fluid balance.

1. **ADH prevents the conversion of angiotensinogen in blood to angiotensin.**
- This statement is incorrect. ADH (Antidiuretic Hormone) does not prevent the conversion of angiotensinogen to angiotensin. Instead, it primarily functions to promote water reabsorption in the kidneys. The conversion of angiotensinogen to angiotensin is actually facilitated by the enzyme renin.

2. **Aldosterone facilitates water absorption.**
- This statement is correct. Aldosterone is a hormone that promotes the reabsorption of sodium and water in the kidneys, which helps to increase blood volume and blood pressure.

3. **The atrial natriuretic factor enhances sodium reabsorption.**
- This statement is also correct. The atrial natriuretic factor (ANF) actually promotes the excretion of sodium (natriuresis) and opposes the action of aldosterone, thus helping to regulate blood pressure and fluid balance.

4. **Renin causes vasodilation.**
- This statement is misleading. Renin itself is an enzyme that catalyzes the conversion of angiotensinogen to angiotensin I, which is then converted to angiotensin II, a potent vasoconstrictor. Therefore, renin does not directly cause vasodilation.

Based on this analysis, the incorrect statement is the first one regarding ADH.

### Step-by-Step Solution:
1. Identify the statements regarding hormones and their functions.
2. Analyze each statement for accuracy based on biological functions.
3. Determine which statement is incorrect based on the roles of ADH, aldosterone, ANF, and renin.
4. Conclude that the incorrect statement is the one about ADH preventing the conversion of angiotensinogen to angiotensin.