The sentence that helps readers determine the story’s setting is:
"The morning mist was completely gone. The sun was strong and bright, intensifying the color of a row of potted marigolds on the front porch of one of the houses."
This sentence provides details about the time of day (morning) and the weather (sunny), as well as visual information about the environment (marigolds on a front porch), which helps to establish the setting of the story.