Relative volatility varies with the concentration of component for an ideal solution. The relative volatity of a binary mixture may be defined as the ratio of vapor pressure of component 'A' to that of component 'B', when%!

• A. Only vapor phase follows Raoult's law
• B. Only liquid phase obeys Dalton's law
• C. Liquid phase obeys Dalton's law and vapor phase obeys Raoult's law
• D. Vapor phase obeys Dalton's law and liquid phase obeys Raoult's law