Answer: what’s the question ?
Hello, the answer in this question is choice C. ( when I simplified both of them they had the same answer which is : 10^4y-8y^3 + 3y)
You get extraneous solutions anytime the radical becomes undefined under the set of real numbers. for example

does not exsist since the radical cannot be used on a negative number
The answers are: M+N/M*N/M*S/N+T