The length of a rectangle is 4r²sāµ units, and the rectangle's area is 20rāµsā· square units. If r ā 0 and s ā 0, which of the following best describes the width of the rectangle?
A. 5r³s² units
B. 5rā·s¹² units
C. 16r³s² units
D. 80rā·s¹² unitsā