Daniel finds a rectangular index card and measures its diagonal to be 8 centimeters. Daniel then cuts out equal squares of side 1 \mathrm{~cm} at two opposite corners of the index card and measures the distance between the two closest vertices of these squares to be 4 \sqrt{2} centimeters, as shown below. What is the area of the original index card?
Answer Choices
A. 14
B. 10 \sqrt{2}
C. 16
D. 12 \sqrt{2}
E. 18