The correct answer is $\boxed{\text{v} = \omega \sqrt{r^2 + y^2}}$.
The velocity of a particle moving in a circle is given by the following equation:
$$\text{v} = \omega r$$
where $\omega$ is the angular velocity and $r$ is the radius of the circle.
In this case, the particle is moving with a uniform angular velocity of $\omega$ radians/sec. The radius of the circle is $r$. Therefore, the velocity of the particle is:
$$\text{v} = \omega r = \omega \sqrt{r^2 + y^2}$$
where $y$ is the distance of the particle from the center of the circle.
Option A is incorrect because it does not include the term $r$. Option B is incorrect because it does not include the term $\omega$. Option C is incorrect because it does not include the term $y$.