The correct answer is B. If the bus is late, he will be late to class.
Explanation:
In grammar, a pronoun is a word that replaces a noun for example she, he, it we; additionally, in sentences it is common these type of words replace a previous noun which is referred as antecedent and for this to be grammatically correct both the antecedent and the pronoun need to agree in gender and number. This implies if the noun presented is "Joseph" which is masculine and singular this can only be replaced by the noun "he" which is also masculine and singular or in the case the noun is "dog" this can be replaced by the pronoun "it".
Considering this, the sentence in which there is not an agreement between the pronoun and the antecedent is "If the bus is late, he will be late to class" because in this, the antecedent is "bus" and this should be replaced by the pronoun "it" that describes animals or objects but instead it has been replaced by "he" which refers to a person.
