Besides adding complementary flavors to many foods, hot sauces stimulate the release of endorphins in the brain, just as exercise does, and these have a pain-relieving effect like morphine's.
关键是选项B, 后面的 effect that is like morphine, 属于 Correctness Mistake 了. 明明应该是 endorphins effect 比较 morphine effect. 不应该是 effect 去比较 morphine. 所以大错特错了.
选项A, 后面的 and these (就近指代endorphins) have a pain-relieving effect like morphine's (指代morphine effect) 注意: 这 morphine effect 短语是修饰前面那个单词 effect. 中文意思: 象(吗啡产生的效果)那样相似的效果
6楼会问: 那为什么不是 mrophine has ? 不是有对应吗? 其实如果是 mrophine has 的话, 那么就不应该是 like 这词,而应该用 as. 因为从所周知么: as A do, B do. 选项A 的like, 并不是什么: like A, B do 只是作为短语 like morphine's 修饰 effect 而已.