If 1 - x^3100 = 3/5 , then x equals to?

Answer: Option B

$$\begin{array}{rl}& \sqrt{1-\frac{x^3}{100}}=\frac{3}{5}\\ & \Rightarrow 1-\frac{x^3}{100}={\left(\frac{3}{5}\right)}^2\\ & \Rightarrow 1-\frac{9}{25}=\frac{x^3}{100}\\ & \Rightarrow \frac{16}{25}=\frac{x^3}{100}\\ & \Rightarrow x^3=\frac{16\times 100}{25}\\ & \Rightarrow x^3=16\times 4\\ & \Rightarrow x^3=64\\ & \Rightarrow \boxed{x=4}\end{array}$$