Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct word or phrase that best fits each of the numbered blanks.
The USA is encouraging Americans to wear face masks. There has been a lot of talk about whether or not face masks are effective in helping slow down the ___(1)___ of the COVID-19 coronavirus. The government is set to encourage Americans to use homemade face covering like cloth masks, bandanas, and scarves. At first, the WHO and some health organizations recommended that people ___(2)___ were not sick didn’t need to wear masks or cover their faces. ___(3)___, it is now proved that face masks can work effectively. They point to countries like Singapore and South Korea, where people wear masks and reported infection ___(4)___ are lower.