P–O–P bond is absent in :-

Options

A. Dimetaphosphoric acid
B. Pyro phosphorous acid
C. Cyclic trimetaphosphoric acid
D. Hypo phosphorous acid

Explanation

To determine where the P–O–P bond is absent, we will analyze the structures of the given compounds one by one.

### Step-by-Step Solution:

1. **Identify the Compounds:**
We have four compounds to analyze:
- A: Dimetaphosphoric acid
- B: Pyrophosphorous acid
- C: Cyclic trimetaphosphoric acid
- D: Hypophosphorous acid

2. **Draw the Structure of Dimetaphosphoric Acid (A):**
- The structure can be represented as:
```
P=O
|
O
|
P-OH
|
P=O
```
- In this structure, we can see that there is a P–O–P bond present.

3. **Draw the Structure of Pyrophosphorous Acid (B):**
- The structure can be represented as:
```
P=O
|
OH
|
O
|
P=O
|
OH
```
- Here, we also observe a P–O–P bond present.

4. **Draw the Structure of Cyclic Trimetaphosphoric Acid (C):**
- The structure can be represented as:
```
P-O-P-O-P
```
- In this cyclic structure, there are multiple P–O–P bonds present.

5. **Draw the Structure of Hypophosphorous Acid (D):**
- The structure can be represented as:
```
P=O
|
H
|
OH
```
- In this case, there is no P–O–P bond present; we only see P–O and P–H bonds.

6. **Conclusion:**
- After analyzing all the structures, we conclude that the P–O–P bond is absent in **Hypophosphorous acid (D)**.

### Final Answer:
The P–O–P bond is absent in **Hypophosphorous acid (D)**.