Experts believe that senior citizens with higher than average cholesterol and their families develop a predisposition to cardiovascular disease are more likely to die at an age below that of their life expectancy.

a) and their families develop a predisposition to cardiovascular disease

b) whose families have a predisposition to cardiovascular disease

c) and a predisposition to cardiovascular disease runs in the family

d) whose families have a predisposition to cardiovascular disease running in them

e) with a predisposition to cardiovascular disease running in their family