答案：C

题目分析：句意：你是在餐馆丢失你的手提袋吗？where you had dinner with me yesterday ，where引导定语从句，修饰并指代前面的名词the restaurant “你和我昨天吃饭的地方” where在从句中作地点状语 只能用关系副词where或者in+which ，不能单纯只用关系代词which或者that ，因为关系代词which或者that在定语从句中只能作主语、宾语。... it be ... that 是强调句型 强调地点状语in the restaurant，选C。