**The correct option is (b) 5.**

**Explanation;**

But, sin x can not be more than 1.

∴ sin x=1/3

It means, value of sin x is positive.

It means, x lies in first and second quadrant.

So, there are 2 values from 0 to 2π.

So, from 0 to 5π, there will be 5 values for x that will satisfy the given equation.