语法与词汇 54.Since Jonas Salk came up with his polio vaccine, infantile paralysis has virtually disappeared from the United States.

A、 survived from
B、 eliminated
C、 discovered
D、 elevated

【正确答案】 C

【答案解析】这句话的意思是：自从乔纳斯-索尔克发明脊髓灰质炎疫苗以来，小儿麻痹症实际上已经从美国消失了。画线短语come up with意为“想出、提出、提供”；discover意为“(首次)发现、发觉、找到”；survive from意为“存活下来”；eliminate意为“清除、根除”；elevate意为“提高、举起”。根据题意，答案为C。