What is a carcinogen? a. a toxin linked to an increased risk of cancer b. a non-carbon based chemical c. a type of pollution that can be traced to a specific source d. a type of pollution that cannot be traced to a specific source

it would (a)

Explanation:

carcinogen is a substance that gives your tissues a higher chance of getting cancer

the number of valence electrons for each molecule or ion is shown beneath the structure. remember hydrogen will not have more than two electrons. this hydrogen is part of a covalent bond (sharing two electrons). a double bond here would cause hydrogen to share four electrons with phosphorus.