Angles and LInes
Adjacent angles are those that have a common vertex and a common side but do not overlap.
Angles 1 and 2 have a common vertex and a common side and they are completely separated by the segment that divides them, so they are adjacent angles.
Complementary angles are those that add up to 180°. Since 1 and 2 are linear angles because they form a line separated by a segment, they are also complementary angles.
Conclusion: There are two valid choices:
Adjacent
Complementary
