Choose the One Alternative That Best Completes the Statement or Answers

Multiple Choice

Choose the one alternative that best completes the statement or answers the question.
Solve the equation
- $\sqrt{\mathrm{x}+7}+5=\mathrm{x}$

A) $\{9,18\}$
B) $\{2\}$
C) $\{2,9\}$
D) $\{9\}$