( 0.03 )^2 + ( 0.21 )^2 + ( 0.065 )^2 ( 0.003 )^2 + ( 0.021 )^2 + ( 0.0065 )^2

Answer: Option B

$$\begin{array}{rl}& \text{According to the question,}\\ & \sqrt{\frac{{\left(0.03\right)}^2+{\left(0.21\right)}^2+{\left(0.065\right)}^2}{{\left(0.003\right)}^2+{\left(0.021\right)}^2+{\left(0.0065\right)}^2}}\\ & =\sqrt{\frac{0.0009+0.0441+0.004225}{0.000009+0.000441+0.00004225}}\\ & =\sqrt{\frac{0.049225}{0.00049225}}\\ & =\sqrt{100}\\ & =10\end{array}$$