Scenario C$.$ A scientist is interested in studying the effects of work from home $($WFH$)$ days on employee productivity. She gives $100$ employees the sales department of company A the new policy where they are given the opportunity to work from home for two days per week with a flexible schedule, and $100$ employees in the sales department of company B receive a typical in$-$office work schedule with the option to work from home only $1$ Friday per month.What type of independent variable is the IV in scenario C$?$ Explain why you think the IV is that type of IV$.$