Coefficient of discharge Cd is equal to (where Cc = Coefficient of contraction, Cv = Coefficient of velocity, and Cr = Coefficient of resistance)$?

• A. Cc ‚àö√≥ Cv
• B. Cc ‚àö√≥ Cr
• C. Cv ‚àö√≥ Cr
• D. Cc/Cr