That time of year thou mayst in me behold
When yellow leaves, or none, or few do hang
Upon those boughs which shake against the cold,
Bare ruined choirs, where late the sweet birds sang.
What time of year is Shakespeare indirectly referring to?
O Winter
Spring
Summer
Fall

I think that Shakespeare is referring to Winter. I think so because he says,
“Yellow leaves, or none, or few do hang. Upon those boughs which shake against the cold.” Which means that the leaves are falling off of the trees and also that the tree stumps are shaking against the cold. All these things happen is winter. Hope this helped!