Critical Reasoning (CR) | Re: Vitamin supplements must be taken regularly over a period of months in

Vitamin supplements must be taken regularly over a period of months in order to be effective. However, some vitamin supplements can cause harmful side effects when taken daily over periods of several months. Therefore, some people who take vitamin supplements should skip a dose of their supplement once a week in order to avoid these side effects.

Which of the following is an assumption required by the argument above?


A. The negative side effects associated