The absolute value of the complex number [tex]z=a+bi[/tex] is [tex]|z|=\sqrt{a^2+b^2}.[/tex]
Consider the complex number [tex]z=-4-\sqrt{2}i.[/tex] For this complex number [tex]a=-4[/tex] and [tex]b=-\sqrt{2}.[/tex]
Therefore, the absolute value of this complex number is
[tex]|z|=\sqrt{(-4)^2+(-\sqrt{2})^2}=\sqrt{16+2}=\sqrt{18}=3\sqrt{2}.[/tex]
Answer: correct choice is B
