$\begin {array} {1 1} (a)\;(A) \: is \: flase,\: (R) \: is\: true \\ (b)\;(A)\: is\: true, \: (R)\; is\: false \\ (c)\;Both \:(A)\: and\: (R)\: are\: true,\: but\: (R)\: is \: not \: the\: correct\: explanation\: of\: (A) \\ (d)\;Both \: (A) \: and\: (R)\: are\: true,\: but\: (R)\: is\: the\: correct \: explanation\: of \: (A) \end {array}$