题目

科学家针对衰老细胞普遍具有的最典型特征增强的溶酶体β半乳糖苷酶（βgal）的活性，设计并合成了被称为SSK1的化合物。当SSK1进入小鼠的衰老细胞后，SSK1的β半乳糖苷键会迅速被衰老细胞的βgal切割，释放具有杀伤性的毒性分子，诱导衰老细胞死亡；当SSK1进入非衰老细胞时，由于细胞中βgal的活性较低，SSK1不会被代谢激话，不会产生杀伤作用。下列相关叙述正确的是（ ）A.SSK1不能降低小鼠组织器官中衰老细胞的数量B.小鼠细胞的衰老是由机体衰老导The salesman showed her several MP3s and she chose ________ one as she didn't want to spend too much money on it.A．the less expensiveB．less expensiveC．the least expensiveD．least expensive