In this scenario, we want to find the standard deviation of the sampling distribution of the sample mean (the sampling population). We will use the formula for the standard error (SE) of the mean, which is given by:
\[ SE = \frac{\sigma}{\sqrt{n}} \]
where:
- \(\sigma\) is the standard deviation of the population,
- \(n\) is the sample size.
Here, \(\sigma = 49\) and \(n = 100\).
Now, let's calculate the standard error:
\[ SE = \frac{49}{\sqrt{100}} = \frac{49}{10} = 4.9 \]
Therefore, the standard deviation of the sampling population (standard error) is 4.9.
The correct answer is 4.9.