Answer:
D
Explanation:
To keep it short, refer to triangle exterior angle theorem.
Edit: If you want the full explanation,
A isn't the answer. The triangle exterior angle states that the measure of the 2 triangle interior add up to the the exterior angle of the other interior angle within the triangle.
Meaning that
measure of angle 1 equal the measure of 3 and 4 combined.
B. is wrong they are equal to each other because angle 2 is equal to angle 2
angle 1 is equal to angle 3 and 4
So they are equal
C.Wrong unless it a 30 60 90 triangle or 45 45 90 triangle, C is wrong
D. is right since measure of angle 4 and angle 3 add up to angle 1, angle 4 would be lesser than angle 1.