If Nyquist plot has a encirclement of (-1 + jo) point, the system is stable if

• A. there are no poles of G(s) H(s) in right-half plane
• B. there is one pole of G(s) H(s) in right-half plane
• C. there is no zeros of G(s) H(s) in right-half plane
• D. none of the above