题目1单选题
设<img src="https://p.ananas.chaoxing.com/star3/origin/bbc2581b1b4ee1fc2aca8a685c3048f3.png">为连续型随机变量,<img src="https://p.ananas.chaoxing.com/star3/origin/dab9c82d5efb9e3273525a01912a16d8.png">为<img src="https://p.ananas.chaoxing.com/star3/origin/bbc2581b1b4ee1fc2aca8a685c3048f3.png">的密度函数,且<img src="https://p.ananas.chaoxing.com/star3/origin/33038e2521aee00f20d6aa0fb1455875.png">存在,则<img src="https://p.ananas.chaoxing.com/star3/origin/33038e2521aee00f20d6aa0fb1455875.png"> =( )A. <img src="https://p.ananas.chaoxing.com/star3/origin/c0a24cf9d938df8e236bb005c9184b3d.png">B. <img src="https://p.ananas.chaoxing.com/star3/origin/8167dabfa46a0700482c4112982e23d7.png">C. <img src="https://p.ananas.chaoxing.com/star3/origin/f4f610ea9a30272d4beb450f8449a6aa.png">D. <img src="https://p.ananas.chaoxing.com/star3/origin/b46238c6f107213bc4c26beb4b24dfd2.png">