The mean \( \mu \) of the number of girls in 10 births is calculated as follows:
\[
\mu = \frac{\sum_{i=1}^N x_i}{N} = \frac{55}{10} = 5.5
\]
The variance \( \sigma^2 \) is calculated using the formula:
\[
\sigma^2 = \frac{\sum (x_i - \mu)^2}{n} = 8.2
\]
The standard deviation \( \sigma \) is then obtained by taking the square root of the variance:
\[
\sigma = \sqrt{8.2} \approx 2.9
\]
Using the range rule of thumb, we calculate the range of non-significant values as follows:
\[
\text{Range} = \mu \pm 2\sigma
\]
Calculating the minimum and maximum values:
\[
\text{Minimum} = 5.5 - 2 \times 2.9 \approx -0.3
\]
\[
\text{Maximum} = 5.5 + 2 \times 2.9 \approx 11.3
\]
Thus, the range of non-significant values is approximately \([-0.3, 11.3]\).
To determine if having 1 girl is significantly low, we check if 1 is within the range of non-significant values:
Since \( 1 > -0.3 \) and \( 1 < 11.3 \), we conclude that 1 girl is not a significantly low number of girls.
The answer is B.
\(\boxed{B}\)