Kristin Has Just Purchased a Small Office That Organizes Trade

Kristin has just purchased a small office that organizes trade shows. She is deciding on which operating system to choose as the "standard" for all computers within the office.
-For comparison purposes, Kristin draws a chart, noting that ____ of personal computers today run Mac OS.

A) 10%
B) 20%
C) 30%
D) 40%