Answer:
l will give all the possibility to this options
Explanation:
d.simile
l will keep this option aside because here two drifference elements have to be compared using word either 'as' or 'like' and we can see in this pharse "Time flies by" these words are not used.
a.metaphor
Here comparison is done. The time is compared with a act of quick flying. So there is possibility this may be the answer.
b.idom
here the pharse clearly signify a meaning that time is running quickly. so this also can be included to the option
c.personification
in this case the time is given a lively characteristics of flying. This may be the answer.
so the highest possibility through my assumption and knowledge, it can be metaphor
