Tobacco products have been identified as mutagens. however, some tobacco users develop cancer and some do not. the reason for this apparent inconsistency is a mutagens only have the capability to cause mutations if exposure lasts over 20 years b. some people are more predisposed to developing cancer when exposed to mutagens c. not all tobacco products are cancerous

Option B

Explanation: A genetic predisposition also known as genetic susceptibility can be defined as the likelihood of developing particular disease based on the genetic makeup of person.

It results from specific genetic predisposition that is inherited from the parents.

It increases the chances of diseases development but do not cause it directly.

So, the correct answer is option B

the correct option is option d

multiple allele inheritance is traits controlled by more than 2 alleles (ex: pigeons having 3 alleles of one gene govern their feather color).   so the answer is a.