Final answer:
The correct change from a simple sentence to a complex sentence is option C, which adds a dependent clause to the original sentence. The review of sentences shows where commas are needed or not necessary for correct grammar.
Step-by-step explanation:
The sentence that correctly changes the simple sentence into a complex sentence is: C. After the basketball game, I made dinner. This is because a complex sentence is made up of an independent clause and one or more dependent clauses connected by a conjunction. In option C, 'After the basketball game' acts as the dependent clause, and 'I made dinner' is the independent clause.
Now, let's review the sentences for appropriate comma usage:
- I finally found my keys, and I got to work just in time.
- Mrs. Contreras threw out her old coffee table and cleaned the carpet. (No comma needed)
- Taking the elevator to the roof, we hoped we could see the skyline and the bay. (No comma before 'and')
- Though Susan wasn't feeling well, she went to the store anyway and bought ice cream, pizza, and candy.
- I let my neighbor borrow my phone because she said hers was tapped by the police. (No comma needed)
To change a simple sentence into a complex sentence, we need to add a dependent clause to the main clause. In this case, the dependent clause 'After the basketball game' is added to the main clause 'I made dinner,' creating a complex sentence.
This adds more information to the sentence and shows a cause-and-effect relationship between the basketball game and making dinner.
Therefore answer is C. After the basketball game, I made dinner.