Which sentence contains both an adverb and a conjunction?  

A. Do you want the shrimp or the crab? 
B. Don't imagine you can't do as you wish. 
C. Lawson crept silently up the stairs, but couldn't still his heartbeat. 
D. Lucille was a kind person, but she hated people who spread rumors. 

About this question,I've thought about it long enough and I would say it has to be C because the conjunction would be "but" and the adverb would be like "how,where,when and why. Am I correct Ms.Sue?

C is correct.

"But" is the conjunction.

Which word tells how she crept up the stairs? Hint: Adverbs often end in -ly.

Silently

Right. :-)

Yes, you are correct! In the sentence "Lawson crept silently up the stairs, but couldn't still his heartbeat," we can identify both an adverb and a conjunction.

The adverb in this sentence is "silently," which describes how Lawson crept up the stairs.

The conjunction is "but," which connects the two clauses "Lawson crept silently up the stairs" and "couldn't still his heartbeat."

Great job on identifying the correct answer!