x% of x is the same as 10% of

Answer: Option B

Let x% of x = 10% of y
Then,
$$\begin{array}{rl}& \Rightarrow \frac{x}{100}\times x=\frac{10}{100}\times y\\ & \Rightarrow y=\frac{x^2}{100}\times 10\\ & \Rightarrow y=\frac{x^2}{10}\end{array}$$