With high hopes, the company sent samples of the substance to scientists, but they couldn't________any practical uses for it.
【正确答案】
A
【答案解析】解析：本题空格处是说科学家们说不出它有任何实用处。A项come up with“赶上，提出”符合题意，如：He couldn’t come up with an appropriate answer just at the time．(那时他想不出一个合适的答案。)其他三项do justice to“公平对待，适当处理”，get even with“报复”，look up to“尊敬，仰望”都不正确。