(单选题)若函数<img src="/lqwvjeImg/19/198d79ef88c104205092a2bb7447425a.png"style="width:48px;height:28px;">区间上连续,则在区间上函数一定存在最大值和最小值的是( )<br>·<img src="/lqwvjeImg/e0/e0da5e0cbfcdbedf5a9f3dc3ebdfb90c.png"style="width:77px;height:30px;"><br>·<img src="/lqwvjeImg/8a/8ac1c7cb5fcbe404f78dff810fcf1f54.png"style="width:46px;height:30px;"><br>·<img src="/lqwvjeImg/a0/a0c84a9a11c43d822dbfedd5ca7ea77d.png"style="width:61px;height:30px;"><br>·<img src="/lqwvjeImg/73/73fc18c8759662be1f4f1f3d12d7c111.png"style="width:62px;height:30px;">