Correct option is C
Given:
∠QBC = 70°
PQ Il AC
Concept used:
The tangent-chord theorem (also known as alternate segment theorem ) states that in any circle, the angle between a chord and a tangent through one of the end points of the chord is equal to the angle in the alternate segment.
Solution:

∠QBC = ∠BQP (PQ Il AC)
With the help of tangent cord theorem
∠BPQ = ∠QBC
So, ∠BQP and ∠BPQ = 70°
So ∠PBQ = 180 - 140= 40°
∴ ∠PBQ is 40°



