A function f(x, y) is said to be homogeneous of degree n in the variables x and y if it can be expressed in the form

• A. \({x^n}\phi \left( {\frac{y}{x}} \right)\)
• B. \({y^n}\phi \left( {\frac{x}{y}} \right)\)
• C. Both 1) and 2)
• D. None of the above