So, first, we should know that the length of OA is 7. Why? It's because OA is a radius and all radius in a specific circle are the same.
Next, we know that length AP is perpendicular to OA. How do we know this? It is because it is stated that AP is a tangent of OA. All tangents are perpendicular.
Knowing this, we could know that it is a right triangle, with lengths 7 and 25 as the legs and hypotenuse
Using Pythagorean theorem, 25^2 = 7^2 + b^2
625 = 49 + b^2
576 = b^2
b = 24
So the length of AP is 24, or answer choice d.
<This is the same message from the same questions you asked>
Hope this helps!