1st one. Mother and father are visiting my sister.
Explanation:
The 1st one is right because mother and father is just a relationship not a place or a name. Mother is in caps because it is in the starting of the sentence. If mother was in the middle of the sentence then it would be lower case. The 2nd option has caps for father so it is wrong.
I am 100% sure this is the answer. Please mark branliest.
Names for people need to be capitalized. A few examples are: Father, Aunt, Mother, etc. In this sentence, Mother and Father are being used in place of names, which makes them capitalized.
