Hi Duolingocom4!!!
Similies are statements that compare two things, usually with the word "like" or "as".
Examples:
Crazy like a fox.
As brave as a lion
So, what two things are being compared in this?
So first we see "time". So that is obviously on of the two being compared. The next thing said is, "like water". So, now we know that time and water are being compared, or, answer A.
I hope I helped! Message me if you need more help :)
~Olivia