The correct answer to this open question is the following.
You forgot to include the options of the question, however, we can answer the following.
A correct analysis of the sentence would be "The prepositional phrase “on the park bench” acts as adjectival phrase."
In this case, the prepositional phrase is going to modify the non that is " the kindly old man." The preposition in the sentence is "on the bench," the place where the old man is seated while feeding the pigeons with breadcrumbs.
It means that something in the blue sky above appears threatening. Whatever the thing in the sky may be is causing you fear! It suggests a horrible danger to come. You better run before it's too late.
You can contribute you knowledge to your generation and generations below you and set standards for your community and the world around you while making a positive impact to society.
