[" 93.Which of the following when simplified,does not reduces "],[" to unity? "],[" (a) "log_(10)5*log_(10)20+log_(10)^(2)2],[" (b) "(2log2+log3)/(log48-log4)],[" (c) "-log_(5)log_(3)sqrt(root(5)(9))],[" (d) "(1)/(6)log_((sqrt(3))/(2))((64)/(27))]