What are next two terms of the GP $\sqrt{2},\;1/\sqrt{2},\;1/2\sqrt{2}$

Question

$(a)\;\frac{1}{4\sqrt{4}},\frac{1}{6\sqrt{2}}\qquad(b)\;\frac{1}{\sqrt2},{\sqrt2}\qquad(c)\;\frac{1}{4\sqrt{2}},\frac{1}{8\sqrt{2}}\qquad(d)\;\frac{1}{4},\frac{1}{4\sqrt{2}}$