Answer: Expression [tex]\sqrt{9}.\sqrt{16}[/tex] will be the correct answer.
Explanation:
Since, we know that a rational Number is a number which can be expressed in the form p/q where q≠0 .
here the option √3×√2=√6 is not a rational number.(because, [tex]=\sqrt{m} \times \sqrt{n}= \sqrt{m\times n}[/tex])
√11×√5=√55 is not a rational number.
√52×√2=√104 is not a rational number.
√9×√16=√144=12 is a rational number. ( because every integer must be a rational number).
So, 4th option will be correct .