which of the following best describes Formularies?

A.A list of approved medications for which an insurance plan will reimburse subscribers
B. Formulas for calculating coinsurance payments
C. A list of generic drug ingredients for use in company medication
D. People who act as gatekeepers in primary care plan

None of your choices matches this definition.

http://www.thefreedictionary.com/formularies

I agree, the term is being mis-used here if it is to mean answer a. However, this term is commonly used to mean approved prescription (or drug) formularies, so answer A is what that is.

Yep, Medicare uses this term (formularies), so it must be so!

The best way to determine the correct answer is to analyze each option and understand its definition.

A. A list of approved medications for which an insurance plan will reimburse subscribers: This definition describes a formulary. It is a list of drugs approved by an insurance plan that determines which medications they will reimburse for their subscribers.

B. Formulas for calculating coinsurance payments: This option does not represent a formulary. Formulas for calculating coinsurance payments refer to the calculations used to determine the portion of healthcare costs that the patient must pay after meeting their deductible.

C. A list of generic drug ingredients for use in company medication: This option refers to the ingredients used in manufacturing company medications and is not related to a formulary.

D. People who act as gatekeepers in a primary care plan: This option describes the role of gatekeepers in a primary care plan rather than a formulary. Gatekeepers are individuals such as primary care physicians who help manage and coordinate a patient's healthcare, usually by providing referrals to specialists.

Based on the definitions provided, the answer that best describes formularies is A. A list of approved medications for which an insurance plan will reimburse subscribers.