Which of the following will not show geometrical isomerism?

Options

A.
B.
C.
D. `CH_3CH=CHCH_2 CH_3`

Explanation

To determine which of the given structures will not show geometrical isomerism, we need to understand the conditions required for geometrical isomerism to occur.

### Step-by-Step Solution:

1. **Identify the Requirement for Geometrical Isomerism:**
- Geometrical isomerism occurs in compounds that have a carbon-carbon double bond (C=C) and different groups attached to each carbon of the double bond. The two types of geometrical isomers are cis (same side) and trans (opposite sides).

2. **Analyze Each Structure:**
- **Structure 1:**
- Contains a C=C double bond with different groups attached to each carbon. For example, if one carbon has a hydrogen (H) and a methyl group (CH₃), and the other carbon has a hydrogen (H) and a chlorine (Cl), then this structure can show geometrical isomerism.
- **Structure 2:**
- Contains a C=C double bond but has the same group (H) attached to one of the carbons. For example, if both groups on one carbon are hydrogen (H), then this structure cannot show geometrical isomerism because the groups are not different.
- **Structure 3:**
- Similar to Structure 1, it has different groups on both carbons of the double bond, allowing for geometrical isomerism.
- **Structure 4:**
- Again, contains different groups on both carbons of the double bond, so it can show geometrical isomerism.

3. **Conclusion:**
- After analyzing all structures, it is clear that **Structure 2** will not show geometrical isomerism because it has identical groups attached to one of the carbons in the double bond.

### Final Answer:
The structure that will not show geometrical isomerism is **Structure 2**.

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