From a historical point of view, what was columbus's most important achievement?

Rank the following from most to least devasting: ordovician,permaian,cretaceous, pleistocene

Persons who have not yet attained the legal age of consent under the applicable laws in the jurisdiction in which the research was approved.persons who are under 18 years of age.persons who have not yet attained the legal age of consent under the applicable laws in the jurisdiction in which the research will be conducted.persons who are under 21 years of age.

Laws that cover individuals who are injured by a product