Among the following three canonical sturetures what would be their relative contribution in hybrid?
`CH_(2)=CH-underset(o+)CH-CH=underset(Ɵ)CH_(2)` (I)
`CH_(2)=CH-CH-CH=CH-CH_(2)` (II)
`overset(o+)CH_(2)-CH=CH-CH=CH-overset(Ɵ)CH_(2)` (III)

Options

A. `IgtIIgtIII`
B. `IIIgtIIgtI`
C. `IgtIIIgtII`
D. `IIIgtIgtII`

Explanation

To determine the relative contribution of the three canonical structures to the hybrid, we need to analyze their stability based on the presence of charges, resonance, and overall structure. Here’s a step-by-step breakdown of the analysis:

### Step 1: Identify the Structures
We have three canonical structures:
1. Structure I: `CH2=CH-CH(+)CH-CH2`
2. Structure II: `CH2=CH-CH-CH=CH-CH2`
3. Structure III: `CH(+)CH2-CH=CH-CH=CH2`

### Step 2: Analyze Stability
- **Structure I** has a positive charge on a carbon atom. This structure is neutral overall and has a double bond, which can contribute to resonance.
- **Structure II** is entirely neutral with no charges. It has alternating double bonds, which allows for resonance stabilization throughout the molecule.
- **Structure III** has a positive charge on one carbon and a double bond. While it has resonance, the presence of the positive charge makes it less stable than Structure II.

### Step 3: Determine Relative Contributions
- **Most Stable Structure**: Structure II is the most stable because it is neutral and has resonance stabilization without any charges.
- **Intermediate Stability**: Structure I is more stable than Structure III because it has a single positive charge and can still participate in resonance.
- **Least Stable Structure**: Structure III is the least stable due to the presence of a positive charge and less effective resonance compared to Structure II.

### Conclusion
The relative contributions of the structures to the hybrid can be summarized as follows:
- Structure II contributes the most to the hybrid (most stable).
- Structure I contributes moderately to the hybrid.
- Structure III contributes the least to the hybrid (least stable).

### Stability Order
The stability order is:
1. Structure II (most stable)
2. Structure I (intermediate stability)
3. Structure III (least stable)