9. Studies show that young people with higher-than-average blood pressure and their families have a history of high blood pressure are more likely than others to develop a severe form of the condition.
(A) and their families have a history of high blood pressure
(B) whose families have a history of high blood pressure
(C) and a history of high blood pressure runs in the family
(D) whose families have a history of high blood pressure running in them（B）
(E) with a history of high blood pressure running in their family
对答案B我有两个疑问：
1，whose 前面不需要一个and 么？
2，with higher-than-average blood pressure 这个介词短语可以和whose families have a history of high blood pressure这个定语从句并列修饰young people 么？
盼指点，谢谢！ | 
