成熟的神经细胞在兴奋时，下列几种酶中最不活跃的是[ ]
A．ATP合成酶
B．DNA聚合酶
C．呼吸酶
D．RNA聚合酶
答案：B
World Wildlife Fund ______ very much the efforts that China has made to protect endangered species from being further endangered.
A．enjoys
B．appreciates
C．thanks
D．prefers
铸18的代号为（）。
A、L18
B、KT18
C、ZZ18
D、Z18
