A3型题 男,37岁。黏液脓血便伴里急后重2年。近1周腹痛加重。体检:体温38℃,贫血貌,左下腹部轻压痛。为明确诊断首选的检查是
A
尿常规 B
血清C反应蛋白 C
血清CA<img border="0" alt="" src="https://img.weimei168.com/uploads/upimg/20230103/13152585_0.gif"><img border="0" alt="" src="https://img.weimei168.com/uploads/upimg/20230103/13152585_0_1.gif"> D
腹部CT E
结肠镜检查