If $A = {\sin ^2}x + {\cos ^4}x,$ then for all real $x$:

Question

${{13} \over {16}} \le A \le 1$

$1 \le A \le 2$

${3 \over 4} \le A \le {{13} \over {16}}$

${{3} \over {4}} \le A \le 1$

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