I guess it would either be mood or syntax
The answer is "stacks." That is the object of the phrase, and since a person is searching for something ON the shelf, they aren't searching for the shelf itself.
It is a A. simple sentence, because there is only one main verb - opened.
A compound sentence has at least two independent clauses, a complex sentence has an independent clause and at least one dependent, a compound-complex clause sentence has two independent clauses and at least one dependent.
you are losing balance
like floating stars
extend your hand to extinguish the fire
a spark enough
you do not complete the road
canes required
take my heart
until forever lover
and words ends
ashes remain backward
don't forget me
HOPE THIS HELPS! :)
She cares about people around her