Given,

(11.92)²+(16.01)²=?²×(3.85)²

It can be approximated as

(11.92)²+(16.01)²=?²×(3.85)²

= (12)²+(16)²≈(?)²×(4)²

= 144+256=(?)²×16

= 400= (?)²×16

= $\frac{400}{16}$=(?)²

=25=(?)²

= 5

Hence, Option D is correct.