Talking about the Weather in Chinese
C is the correct answer.
Analysis:
“是(shì)” is an equative-verb which equates two nouns (or nominal expressions) as in: “我是美国人(Wǒ shì měiguó rén), I am American.” “下雨(xiàyǔ), to rain” is not a noun. In this case, “今天是下雨(Jīntiān shì xiàyǔ)” is not a correct sentence. “雨(yǔ), …