I think it’s We
Hope this helps
The correct answer would be B. "My father" can be replaced with the pronoun "He." Answers C and D are incorrect because the speaker is not the father, and A is incorrect because "His" refers to something the father owns, not the father. Also, you can plug in each pronoun and see which ones sound fluent. Hope this helps! :)
It's mostly written in 1st person if I remember correctly.