Which Is the Most Definitive Diagnostic Test for Polymyositis and Dermatomyositis

question 3

Multiple Choice

Which is the most definitive diagnostic test for polymyositis and dermatomyositis?

• A) Muscle biopsy
• B) Western blot test
• C) Immunofluorescent assay
• D) Dual-energy x-ray absorptiometry (DEXA) scan

---

Definitions:

Marginal Revenue

The extra revenue generated by the sale of an additional unit of a product or service.

Monopolist

An individual or business entity that is the sole provider of a particular good or service, enabling control over market prices.

Inverse Demand Function

A mathematical function that expresses price as a function of quantity demanded, illustrating how price varies with changes in demand.

Total Costs

The complete cost of production that includes both fixed and variable costs.