题目7单选题
设<img src="https://tihai-oss-cloud.itihey.com/img/2617871055f9ee65885fd78c00849a05.png">为随机变量X的分布函数,则 ( )A. <img src="https://tihai-oss-cloud.itihey.com/img/2617871055f9ee65885fd78c00849a05.png">连续B. <img src="https://tihai-oss-cloud.itihey.com/img/2617871055f9ee65885fd78c00849a05.png">不增C. <img src="https://tihai-oss-cloud.itihey.com/img/2617871055f9ee65885fd78c00849a05.png">右连续D. <img src="https://tihai-oss-cloud.itihey.com/img/2617871055f9ee65885fd78c00849a05.png"> 左连续