Best and correct answer gets brainliest.

I think its C, only because its 180 degrees in a triangle . 80 plus 30 makes 110 so yeah . 

ΔXYZ is congruent to ΔPQR.
Therefore they have the same dimension on the corresponding parts, and they have the same measurement of angles on the corresponding parts.
∠X = ∠P = 30°
∠Y = ∠Q = ?
∠Z = ∠R = 80°

To find the measurement of ∠Y, use interior angles sum property.
The sum of interior angles on a triangle is equal to 180°
∠Y + ∠X + ∠Z = 180°

plug in the numbers
∠Y + 30° + 80° = 180°
∠Y + 110° = 180°
∠Y = 180° - 110°
∠Y = 70°

The measurement of ∠Y is 70°
The answer is third option