Comparing with one fador authentication, two$-$factor autherticationprovides more protection to the user identity in online services. Please compare three different types of ourrenty avalable techniques for secondfactor with regarding to$($a$)$ Password cracking$($b$)$ Eavesdropping$($c$)$ Loss of second factor$($d$)$ Trojan horse or Key logging$($e$)$ Men$-$in$-$the$-$Middle preventon