Answer:
C. he and she
Explanation:
In this sentence, "my father" and "my mother" are the subjects that perform the action which is "discuss". As they are the subjects of the sentence, it's necessary to use the subject forms of the pronouns: "he" and "she".
Another way to put it is by separating the original sentence in two sentences:
- He rarely discuss politics with my mother.
- She rarely discuss politics with my father.
So:
He and she rarely discuss politics.
The effect of the underlined section in developing the tone
of this excerpt from "In a Queen's Domain" by Sarah Morgan Bryan
Piatt is it helps to change the tone of the poem from calm and carefree to
sinister and menacing.