Answer:
The sentence that is complex is:
C. After Danny and Erica rode their bikes throughout the countryside, they went back to Erica's house and had some cool lemonade.
Explanation:
A complex sentence is formed by joining an independent clause to a dependent or subordinate one. An independent clause is able to stand alone as a sentence because it can convey a complete thought on its own. A dependent clause on the other hand, cannot do that. Alone, it sounds incomplete.
<u>The sentence "After Danny and Erica rode their bikes throughout the countryside, they went back to Erica's house and had some cool lemonade" is an example of a complex sentence. The independent clause is:</u>
<u>- they went back to Erica's house and had some cool lemonade</u>
<u>The dependent clause is the one beginning with a subordinating conjunction (after), and which cannot stand alone as a sentence:</u>
<u>- After Danny and Erica rode their bikes throughout the countryside</u>
