C. 70°
Step-by-step explanation:
93 is as internal angle the supplementary angle to the external angle at that point (together they are 180°).
the sum of the exterior angles of a polygon is 360°.
we have here
52°
180-93 = 87°
x+3
78
x
so,
52 + 87 + 78 + x + 3 + x = 360
220 + 2x = 360
2x = 140
x = 70°