I will share with you a story happened a few days ago. One of my classmate bought a bag of snacks from a food store. A few roommates were then invited to enjoy snacks. Unluckily, all of them got poisoned and had stomachaches with our faces pale. They are quickly sent to a nearby hospital. Doctors examined them but gave them some medicine. They were out of danger soon before taking the medicine. This accident should make us to realize the seriousness of the food safety problem. I strong suggest that the whole society pays more attention to food safety.

下列哪项符合单纯性甲状腺肿特点（）

A.甲状腺弥漫性肿大

B.甲状腺结节性肿大

C.吸¹³¹I率正常的甲状腺肿大

D.甲状腺功能正常的甲状腺肿大

E.慢性甲状腺炎引起的甲状腺肿大