The following text is from an unpublished memoir.
Some mornings the lake is empty, no fishermen, no rowboats—only the thin call of loons. Those are the mornings I like best, when the water lies still enough to reflect every cloud and I can imagine the entire shoreline is mine alone. Dad says it's selfish to want a place to yourself, that lakes are for sharing. I nod, but I also notice how quiet he grows on the dock before anyone else arrives.
Which choice best states the main purpose of the text?