[单选题]
A car is moving with a constant speed v around a levjv 4: nre7nf6jel curve. 2 bld 4x5t5bsgThe coefficient of friction between th4 s bglx255bdte tires and the road is 0.40. What is the minimum radius of the curve if the car is to stay on the road?
A. $0.40v^2/g$
B. $v^2/g$
C. $2.5v^2/g$
D. $2v^2/g$
