TOEICクイズスレ

241 ：Mr.QZ ◆WBRXcNtpf. ：2016/05/12(木) 00:05:58.06 ID:8lfcE+ly.net

The quality of the rubber seal on the machine's casing has ----- because it was repeatedly exposed to excessive heat.

A. aggravated
B. malfunctioned
C. deteriorated
D. vacated