Sonja Used to Work Out Five Days a Week When

Sonja used to work out five days a week when she was in her late teens.In her twenties,she worked out three days a week.Now she is in her forties,and she seems to work out only when she has the time.Which trend does Sonja's pattern of behaviour illustrate

A)  Many health-impairing habits creep up on us. 
B)  People underestimate the risks associated with their health-impairing behaviours. 
C)  The risks associated with health-impairing habits tend to lie in the distant future. 
D)  Many health-impairing habits involve activities that are quite pleasant at the time.