If the direction ratios of a line are 5, 4, -7 respectively, then find the direction cosines.

• A. ( frac{75}{ sqrt{90}}, frac{4}{ sqrt{90}}, frac{5}{ sqrt{90}} )
• B. ( frac{5}{ sqrt{90}}, frac{4}{ sqrt{90}},- frac{7}{ sqrt{90}} )
• C. ( frac{5}{ sqrt{70}}, frac{4}{ sqrt{70}},- frac{7}{ sqrt{70}} )
• D. ( frac{3}{ sqrt{90}}, frac{4}{ sqrt{90}},- frac{5}{ sqrt{90}} )