14.WhileA he thinks the phenomenonB is the result of enzyme action, I believe it is caused byC a shortage ofD a neurotransmitter. No errorE., a+ v& k9 C& Q" F
. A: \- G; E0 ]: q8 j- s. `$ ?
答案是A,,我郁闷了,WHILE可以当虽然讲,但答案是这样说的 While should be used for simultaneous actions. Change to though.