Nitrous oxide `(N_(2)O)` may be represented by the following structures
`underset((a))(overset(-):underset(..)N=N^(+)=overset(..)O":")harrunderset((b))(":"N-=N^(+)-overset(..)underset(..)O:^(-))harrunderset((c))(overset(2-):overset(..)underset(..)N-N^(+)-=O:^(+))`
Which of these contributes least?

Explanation

To determine which structure of nitrous oxide (N₂O) contributes the least to its resonance hybrid, we need to analyze the three given structures based on certain stability criteria.

### Step-by-Step Solution:

1. **Identify the Structures**:
- Structure A: \( \overset{(-)}{N} = N^{+} = \overset{..}{O} \)
- Structure B: \( \overset{..}{N} - N^{+} - \overset{..}{O}^{(-)} \)
- Structure C: \( \overset{2-}{N} - N^{+} = O^{(+)} \)
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