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 problem.
-Two angles of a triangle are 50° and 100°. What is the measure of the third angle?

A) $210 ^ { \circ }$
B) $150 ^ { \circ }$
C) $- 60 ^ { \circ }$
D) $30 ^ { \circ }$