Final answer:
Option C is identified as a run-on sentence because it contains two independent clauses joined by just a comma. Similarly, Option D is also a run-on sentence due to the lack of punctuation between its independent clauses.
Step-by-step explanation:
The question requires identifying a run-on sentence from the given options. A run-on sentence occurs when two independent clauses are joined without appropriate punctuation or conjunction. After reviewing the options:
- Option A is a complex sentence, not a run-on.
- Option B is correctly punctuated and not a run-on.
- Option C is a run-on sentence because it joins two independent clauses with a comma instead of a semicolon or a conjunction.
- Option D is also a run-on sentence because it lacks the necessary punctuation between independent clauses.
For example sentences presented for review, missing commas should be inserted or incorrectly placed commas omitted to correct the sentence structure. These sentences can help to understand the concept of a run-on sentence and the importance of proper punctuation.