Question

The idea of placing meat on a bun, however, came from the united states

Answer 1

The correct answer is A.

Although it may look like a compound sentence, this is actualy a simple sentence, since it only has one clause.

One subject: the idea of placing meat on a bun;

and one predicate: came from the united states.

The world "however" is part of the predicate, but it's not contrasting two clauses. In this case, it is contrasting the whole sentence with a previous one.

Answer 2

either complex or compound complex                                                                        but for it to be complex there has to be an independent clause

so not really sure