Final answer:
The question involves what activity people have started doing that was previously done by Mrs. Ellison. The context suggests that this activity involves community sharing, such as leaving food in mailboxes. Although there is not a clear reference to the specific options, the mention of cherries points toward the act of leaving food.
Step-by-step explanation:
The question asks about what activity people had begun to engage in that was previously done only by Mrs. Ellison. Based on the context provided, it's clear that there is a communal involvement in a particular practice that Mrs. Ellison used to do alone. Given the various hints from the passages, such as a reference to cherries, which suggests canning or preserving food, and an implication of community involvement similar to leaving food in mailboxes, the answer appears to relate to an act of sharing or hospitality within a community.
Without a direct reference to the options provided (baking pies, delivering mail, leaving food in mailboxes, or planting flowers), it's necessary to infer based on the provided quotes. The reference to cherries from the text appears to imply that people had started leaving food in mailboxes, an act of kindness and community sharing.