Which of the following is correct for phosphorus ?
(i) it occurs in minerals of the apatite family which are the main components of phosphate rocks.
(ii) It is an essential constituent of animals and plant matter
(iii) It is present in bones as well as in living cells.
(iv) Phospho proteins are present in milk and eggs.

Options

A. (i),(ii),(iii)
B. (i),(ii),(iii),(iv)
C. (ii),(iii),(iv)
D. (ii),(iii)

Explanation

To determine which statements about phosphorus are correct, let's analyze each statement one by one.

### Step 1: Analyze Statement (i)
**Statement (i):** "It occurs in minerals of the apatite family which are the main components of phosphate rocks."

- Phosphorus is indeed found in minerals of the apatite family, such as fluorapatite (Ca5(PO4)3F) and hydroxyapatite (Ca5(PO4)3(OH)). These minerals are significant components of phosphate rocks, which are mined for phosphorus.

**Conclusion:** Statement (i) is correct.

### Step 2: Analyze Statement (ii)
**Statement (ii):** "It is an essential constituent of animals and plant matter."

- Phosphorus is a vital nutrient for both plants and animals. It is a key component of DNA, RNA, and ATP (adenosine triphosphate), which are essential for energy transfer and genetic information in living organisms.

**Conclusion:** Statement (ii) is correct.

### Step 3: Analyze Statement (iii)
**Statement (iii):** "It is present in bones as well as in living cells."

- Phosphorus is a major component of bones, primarily in the form of calcium phosphate (Ca3(PO4)2). It is also present in living cells, where it plays a crucial role in cellular functions and metabolism.

**Conclusion:** Statement (iii) is correct.

### Step 4: Analyze Statement (iv)
**Statement (iv):** "Phospho proteins are present in milk and eggs."

- Phosphoproteins are indeed found in milk and eggs. These proteins contain phosphate groups and play important roles in biological functions, including nutrient storage and transport.

**Conclusion:** Statement (iv) is correct.

### Final Conclusion
All four statements about phosphorus are correct. Therefore, the answer is that all statements (i), (ii), (iii), and (iv) are true regarding phosphorus.

### Summary of Correctness
- (i) Correct
- (ii) Correct
- (iii) Correct
- (iv) Correct

### Final Answer
All four statements about phosphorus are correct.

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