China is the only nuclear state ________ not to be the first to use nuclear weapons or to use nuclear weapons against non－nuclear weapon states.
A．undertaking B．to undertake
C．having undertaken D．undertaken
China is the only nuclear state ________ not to be the first to use nuclear weapons or to use nuclear weapons against non－nuclear weapon states.
A．undertaking B．to undertake
C．having undertaken D．undertaken
B [句意：中国是唯一的核国家承诺不首先使用核武器，不对无核国家使用核武器。当名词被序数词或only等词修饰时，其后用不定式作定语。]