Integrate : $\int \sqrt {\large\frac{1-x}{1+x}}.\frac{1}{x}$$dx$

Question

$(a)\;\log |\frac{1-\sqrt {1-x^2}}{x}|-\sin ^{-1} x+c \\(b)\;-\cos^{-1}x+c \\(c)\;\log |\frac{1-\sqrt {1-x^2}}{x}|- \tan ^{-1}x + c \\ (d)\;None$