The correct answer is B. I met with the admissions counselor at the college, and then I began to apply for financial aid.
Step-by-step explanation:
The comma (,) is a punctuation mark mainly use to separate two ideas that are related and introduce a short pause. According to grammar, comma should be placed before coordinating conjunctions, this includes words as but, for, not, yet, and, especially when the comma is used for linking to independent clauses which are sentences with a subject, verb, and complement, also, commas are used for separating items in a list; after certain adverbs such as finally, however, firstly; before negations in a sentence, among others. Thus, in the case of "I met with the admissions counselor at the college, and then I began to apply for financial aid." comma is used correctly because it is placed after a coordinating conjunction "and" that is separating two independent clauses "I met with the admissions counselor at the college" and "I began to apply for financial aid", which according to grammar is the correct use of comma.