Why would a health insurance company charge a higher premium to a tobacco user? Tobacco use is a voluntary behavior.
Without higher premium prices for tobacco users, nonusers end up paying for users' claims.
Tobacco use causes significant health issues.
Using tobacco products is very expensive.
Tobacco users are at a higher risk of failing to pay their premiums on time.

Tobacco use causes significant health issues.

Explanation:

When insurance coverage commences, the insurance company assumes all the risks associated with the insurance policy issued.  For medical insurance, the insurance company will cater to the insured medical bills should the need arise. For this reason, insurance firms evaluate different risk parameters when deciding on the premiums to charge for insurance coverage.

Tobacco is known to cause health issues in smokers.  Tobacco smokers are more likely to develop health complications at some point in their life. They present a higher risk for insurance companies. Insurance companies will charge them higher premiums to cover the increased risk caused by smoking tobacco.

the answer should be a)

answer: a. the kind of population living in your neighbourhood.

the census explorer data tool by the us census bureau allows the user to zoom in on any neighbourhood within the united states and find the kind of people residing in that by race and age.  

the tool needs to needs to be used twice – once in order to find what type of people reside in a neighbourhood, and then to see the age groups of the people in the same neighbourhood.