Question

WZ←→− is tangent to circle O at point B.

Answer 1

A tangent (here WZ in the question) to any circle (here O in the question) is a line segment that touches the circle at only one point (here B in the question) on circumference of circle, and the radius of the circle (here OB in the question) through this point is always perpendicular to that particular tangent.

In other words, Tangent (WZ) and Radius (OB) of any circle (O) always make a Right angle at point of intersection (B) on its circumference.

It means angle ∠OBZ would be a Right angle i.e. 90 degrees.

So, option B i.e. 90 degrees is the final answer.

Answer 2

The answer to this is 90°