题目1单选题
<img src="https://tihai-oss-cloud.itihey.com/img/9a75cd12e2c39a5fe173ca493708a24a.png">A. 极小值<img src="https://tihai-oss-cloud.itihey.com/img/335d4bdeacfe0728d7d78a182be67ed8.webp">B. 极小值<img src="https://tihai-oss-cloud.itihey.com/img/b0c8f5c796cdf03168d77baef1fd6325.webp">C. 极大值<img src="https://tihai-oss-cloud.itihey.com/img/335d4bdeacfe0728d7d78a182be67ed8.webp">D. 极大值<img src="https://tihai-oss-cloud.itihey.com/img/b0c8f5c796cdf03168d77baef1fd6325.webp">