阅读下面短文，从每题所给的A、B、C、D四个选项中选出最佳选项。

Wuhan is the capital of Hubei. It is a beautiful and large city in China. During the spring Festival of 2020, many people there were in hospital because of the novel coronavirus （新冠病毒）. Many nurses work day and night. They are very brave and kind. People often call nurses the "angels in white". But do you know？The nurses working in hospital don't always wear white clothes. ______Nurses wholook afterchildren often wear pink. Nurses working in operating rooms （手术室）wear green. Those who take care of old people often wear blue.