Sage measured her rectangular house as 15.24 m long and 9.1 m wide. Using her calculator, she multiplied the length by the width to determine that the area is 138.684 m2. What should she do next to express this value in proper significant digits?

A. Record all the digits her calculator shows

B. Round to the last significant place in the least accurate measurement

C. Round to the number of digits in the least significant value.

D. around to as many digits as the largest value.