Crushing efficiency of riveted joint is given by

• A. \(\frac{p/d}{t}\)
• B. \(\frac{\pi~\times~ d^2~\times~ \tau }{p~\times~ t~\times~ \sigma _t }\)
• C. \(\frac{p}{p~-~d}\)
• D. \(\frac{n~\times~ d~\times~ t~\times~\sigma_c}{p~\times~ t~\times ~\sigma_t}\)