Question

what has scientific research consistently shown about nicotine?
nicotine is addictive to everyone, regardless of age.
nicotine is only addictive for adults over the age of.
nicotine is addictive only in laboratory animals.
nicotine is not addictive at all.

Explanation:

Scientific research has consistently shown that nicotine is addictive to humans of all ages, not just adults over a certain age, and not only in laboratory animals. It is a well - established fact that nicotine is addictive.

Answer:

Nicotine is addictive to everyone, regardless of age.