Answer the following question given this paragraph: 

Diseases of the cardiovascular system are common and may be life threatening. Examples include atherosclerosis and coronary heart disease. A healthy lifestyle can reduce the risk of such diseases developing. This includes avoiding smoking, getting regular physical activity, and maintaining a healthy percent of body fat.


Q: Atherosclerosis and coronary heart disease are examples of what type of body system disease?

 Choices:

- connective system

- digestive system

- excretory system

- cardiovascular system

A:
cardiovascular system
