I think it’s A because that is the only one that sounds right
Answer:
gerund is a type of verbal that ends in -ing and is used like a noun. Examples of gerunds include actions like chewing, writing, whispering, and snoring. Similar to infinitives, gerunds can also function as the subject of the sentence, the direct object, or as the subject complement.Types of gerunds
Subjects.
Predicate Nominative.
Direct object.
Object of preposition.
Explanation:
hope this helps
A) before the pony express people couldn’t send mail to the west coast.