On the unit circle, where 0 < theta < or equal to 2pi, when is tan theta undefined?A. Theta=pi and theta=2piB. sin theta = cos thetaC. theta = pi/2 and theta=3pi/2D. sin theta = 1/cos thetaPlease answer within 5 minutes, this is timed.

The tangent is the slope so is undefined when there's no slope, which means a vertical angle, 90 degrees or -90 degrees aka 270 degrees. In radians that's pi/2 and 3pi/2, choice C