Answer:
Complementary angles
Explanation:
When two angles add up to 90°, they are Complementary to each other.
Here, ∠DAB = 90° (right angles)
It means, ∠DAB = ∠BAE (vertically opposite angles)
Also, ∠BAE = a + b
So, a+b is equal to 90°. Hence, the correct option is (b) "Complementary angles".