Here are some superheroes in the fight against COVID-19（新冠肺炎）.Let's come close to them and remember them.
Zhong Nanshan（1936.10-）
He is a doctor and also one of the famous medical scientists in the 21st century.Dr.Zhong Nanshan was the first to tell the public that the virus could be transmitted（传播、传染）from person to person.He is a good doctor in the country men's eyes and respected by all Chinese people.
Li Lanjuan （1947.09-）
When COVID-19 broke out,she suggested that Wuhan should be locked down immediately to prevent the spread of the disease.She headed for Wuhan and took an active part in the battle.Now,she still work as a doctor and receives patients every day.
Wang Yong （1985.12-）
As a delivery（快递）driver,he volunteered to support the medical staff（员工）in Wuhan during the epidemic （疫情）.He tried his best to keep life going for the doctors and nurses.Time magazine has put on its cover,presenting the courage and hard work of common people.
Li Wenliang （1985.10-2020.02）
He is the first doctor to warn people how dangerous the virus could be at the end of December in 2019，so people call him the "whistle-blower"（吹哨人）.Because of COVID-19，he lost his life on February 7th,2020.People across the country were sad to hear about his death.



How many of them are doctors in the passage？ ______

A. One.
B. Two.
C. Three.
D. Four.

What did Wang Yong do during the epidemic（疫情）？ ______

A. He drew a cover for Time Magazine.
B. He was busy with his own business.
C. He wrote an article to Time magazine.
D. He volunteered to support to the doctors and nurses to keep their life going.

When did Li Wenliang warn people the danger of the virus？ ______

A. At the end of December in 2019.
B. At the beginning of 2019.
C. On January 25th,2020.
D. On February 7th,2020.