Let O be the centre of a circle and P be the point outside the circle. If PAB is a secant to the circle intersecting the circle at A and B and PT is the tangent segment drawn from P, find the length of PT, if PA = 3 cm and AB = 9 cm.

A

8cm

B

6 cm

C

$$4\sqrt{3}$$ cm

D

$$3\sqrt{3}$$ cm