Answer:
The correct option is 4. The angle 3 and 6 are vertical angles.
Explanation:
Two angles are called adjacent angles if they have a common side.
Two angles are called complementary angles if their sum is 90 degree.
Two angles are called supplementary angles if their sum is 180 degree.
If two lines intersect each other, then their opposite angles are known as vertical angles and vertical angles are always congruent.
From the given figure it is noticed that angle 3 and 6 are vertical angles because these are opposite angles of intersection of two lines. Therefore option 4 is correct.