Tonya had sold eight boxes of cookies by the time she realized the money envelope had been lost. Which revision corrects the inappropriate shift in verb voice?

A. Tonya had sold eight boxes of cookies by the time the money envelope was realized to have been lost.

B. Tonya lost the money envelope and realized it after eight boxes of cookies had been sold.

C. Tonya had sold eight boxes of cookies by the time she realized that she had lost the money envelope.

D. Eight boxes of cookies had been sold by Tonya by the time she realized she had lost the money envelope.​