Consider a feedback system with gain margin of about 30. At what point does Nyquist plot crosses negative real axis?

A. -3

B. -0.3

C. -30

D. -0.03

I got this question in my homework.

Query is from Nyquist Stability Criterion in division Stability in Frequency Domain of Control Systems

Right choice is B. -0.3

To explain: Gain Margin is always inverse of the point which cuts the Nyquist on the real axis.