JEE Advance - Mathematics (1980 - No. 5)

Given $$A = {\sin ^2}\theta + {\cos ^4}\theta $$ then for all real values of $$\theta $$

$$1 \le A \le 2$$

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

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

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