Which of the following sentences contains a word that is spelled incorrectly?
A.
This diet pill guarantees that you will lose ten pounds in one week.
B.
The phone company asked its customers to complete a questionnaire about the new products.
C.
The skier was rather skillful as she maneuvered through the slalom poles.
D.
You should follow the maintnance schedule for your car in order to prevent major problems.