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