5. Which of the following is a complex sentence?

A. I would like to visit the Kinshasa, but I understand the city is unsafe for foreigners.
[B. As Jake was reading the letter from June yet again, the flight attendant coughed gently to get his attention.]
C. Check out the editorial page in today's paper and you'll notice the piece by Oscar Lewis.
D. I simply cannot make heads or tails of rap lyrics, but I suppose I'm just too old to understand them.

Correct.

A. I would like to visit Kinshasa, but I understand the city is unsafe for foreigners.

To determine which of the given sentences is a complex sentence, we need to understand what a complex sentence is. A complex sentence is a sentence that contains an independent clause and at least one dependent clause.

Let's analyze the options provided:

A. "I would like to visit Kinshasa, but I understand the city is unsafe for foreigners."
This sentence contains two independent clauses connected by the coordinating conjunction "but." The two independent clauses are "I would like to visit Kinshasa" and "I understand the city is unsafe for foreigners." Therefore, option A is not a complex sentence, as it is a compound sentence.

B. "As Jake was reading the letter from June yet again, the flight attendant coughed gently to get his attention."
This sentence contains a dependent clause "As Jake was reading the letter from June yet again" and an independent clause "the flight attendant coughed gently to get his attention." Since it has both an independent and a dependent clause, this option is a complex sentence.

C. "Check out the editorial page in today's paper, and you'll notice the piece by Oscar Lewis."
This sentence is a compound sentence as it consists of two independent clauses connected by the coordinating conjunction "and." Neither of the clauses is dependent on the other, so it is not a complex sentence.

D. "I simply cannot make heads or tails of rap lyrics, but I suppose I'm just too old to understand them."
This sentence is also a compound sentence as it contains two independent clauses connected by the coordinating conjunction "but." Neither of the clauses is dependent on the other, so it is not a complex sentence.

Answer: The complex sentence is option B. "As Jake was reading the letter from June yet again, the flight attendant coughed gently to get his attention."