The waiter took the plates . . . . . . . . after we had finished eating.

The correct answer is: B. off

The waiter took the plates off the table after we had finished eating.

The other options are incorrect because:

• A. up is not a common way to say that someone took something off of a table.
• C. away could be used to say that someone took something away from the table, but it is not as common as “off.”
• D. out is not a common way to say that someone took something off of a table.

I hope this helps! Let me know if you have any other questions.