Exhaled Gas Is Collected for 5 Minutes;the Mixed Expired PCO₂

Exhaled gas is collected for 5 minutes;the mixed expired PCO₂ is measured.Blood gases are drawn during the last minute of gas collection,and the following data are recorded: What is this subject's V_D/V_T ratio?

A) 0.75
B) 0.33
C) 0.25
D) 0.11