Answer
See explanation
Work Step by Step
A) b is the $n$th root of a.
B) Yes because a square root is always taken as the positive root.
C) There are two real roots if even and 1 if odd.
D) The expression$\sqrt[-4] {-2}$ is not real because a fourth power is always non negative. The second is real because negative numbers are defined for all odd roots.
