Choose the correct answer to complete the sentence.
two adjacent, supplementary angles form a(n)
a.) right angle
b.) obtuse angle
c.) line

The best and most correct answer among the choices provided by your question is the third option or letter C. Two adjacent, supplementary angles form a line.

Supplementary angles always have a sum of 180 degrees. Therefore, when these two angles are adjacent, they form a line, which has also an angle of 180 degrees. 

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