Answer: To help slow down the spread of the virus
Explanation:
Believe it or not, this sentence is simple.
Yes, it is quite long, but it has one subject (daylilies) and one verb (are). As a result there is one independent clause.
This single independent clause has some adverb and adjective phrases, but the sentence is still a simple one.

<h3>Active voice:</h3>
People believe that Pluto is no more a planet.
<h3>Passive voice:</h3>
It is believed by people that Pluto is no more a planet.
