The correct answer is B. 1.16%.
The coefficient of variation is a measure of the relative dispersion of a set of data points, expressed as the ratio of the standard deviation to the mean. It is a unitless measure, so it can be used to compare the variability of different sets of data with different units of measurement.
In this case, the standard deviation is 18% and the expected return is 15.5%. The coefficient of variation is therefore:
$CV = \frac{18\%}{15.5\%} = 1.16$
This means that the standard deviation is 1.16 times the expected return. In other words, the returns are expected to vary by 1.16 times as much as the expected return.
Option A is incorrect because it is the standard deviation, not the coefficient of variation.
Option C is incorrect because it is the expected return, not the coefficient of variation.
Option D is incorrect because it is a negative number, which is not possible for the coefficient of variation.