单选题 Many citizens appealed to the city government for enacting ______ laws to protect the consumers.

【正确答案】 C
【答案解析】rigorous严格的,严酷的;equivocal模棱两可的,意义不明确的;stringent严厉的,迫切的;furtive偷偷摸摸的,秘密的。