Which of the following pairs are diastereomers?

Options

A. `{:(" "CHO" "CHO),(" | |"),(H-C-OH and HO-C-H""),(" | |"),(" "CH_(3)" "CH_(3)):}`
B.
C.
D. All of these

Answer

To determine which of the given pairs are diastereomers, we need to follow these steps:

### Step 1: Understand the Definition of Diastereomers
Diastereomers are stereoisomers that are not mirror images of each other. They have different physical properties and are not related as enantiomers.

### Step 2: Analyze Each Pair
We will analyze each pair of compounds provided in the question to determine if they are diastereomers.

1. **Pair A**: Check if they are mirror images.
2. **Pair B**: Check if they are mirror images.
3. **Pair C**: Check if they are mirror images.
4. **Pair D**: Check if they are mirror images.

### Step 3: Identify the Pairs
- **For Pair A**: If the compounds are mirror images, they are not diastereomers.
- **For Pair B**: If the compounds are mirror images, they are not diastereomers.
- **For Pair C**: If one is a cis isomer and the other is a trans isomer, they are not mirror images and thus are diastereomers.
- **For Pair D**: If the compounds are mirror images, they are not diastereomers.

### Step 4: Conclusion
After analyzing the pairs, we find that only **Pair C** consists of diastereomers because they are cis and trans forms of the same compound, which are not mirror images of each other.

### Final Answer
The correct answer is **Option C**, as it contains the pair of diastereomers.

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