Answer:
Compound sentence
Explanation:
A compound sentence is a group of words that consists of at least two independent clauses. The main difference between simple and compound sentences is that a simple sentence is composed of a single clause whereas a compound sentence is composed of two or more clauses. This means that it's a compound since "Frank's favorite drink is coke" is the first independent clause, and "but the restaurant only has Pepsi", is the second independent clause.
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