Let's understand the problem using two method (Refer below image for nomenclature)
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Method 1Angles drawn by joining a point to other points on a line will be maximum (90º) when the point is connected using a perpendicular line and the angles will become (< 90º) smaller as we start going away from the perpendicular pointEx: From point C if we start drawing lines to make angles on the line connecting ADB then ∠ABD = 90º, and angles will start becoming smaller as we start going farther from B.
So, ∠CAB < ∠CDB < ∠ABD
=> xº < yº
Method 2Let's look it from C
Clearly, ∠BCD < ∠BCA
=> -∠BCD > -∠BCA
=> 90º - ∠BCD > 90º - ∠BCA
=> yº > xº
=> xº < yº
So, answer will be B
Hope it helps!