A remarkable concurrence of events or circumstances without apparent causal connection.
The answer is B. Imagery is like... it the thing that helps you picture things in your imagination, hence the word imagery. It's always descriptive. Hope that helps you in the future on how to tell what imagery is.
Another perspective of the poem could what the girl is thinking, or what the lady at the store is thinking or said, or even a father or stranger that had contact (just talked to them) with them for a bit.
It was a usual Saturday. David enters the home through the window as his mother is not at home. David has planned to play cards with his mother. He finds the faded Lily plant. He realized that he hasn't watered it since many days. With the little steps into the home, he suspects the entire home covered with dust and curtains. He wonders, how and why?
He runs towards his aunt's house and confronts to his aunt. He explains in a rush that on every Saturday he used to play cards with his mom, he used to eat fries, he used to watch 'Small Wanders' and there used to be a Lily plant. But all used to be. David's eyes got wet and he bursts into tears. David used to have a family and a good memory. Now David is all alone and he used to have memories.