Mathmate has given you a correct answer -- in fact better than your choices. If you can reduce a fraction, you really should. 11 42/99 is correct and you should pick C. But the better answer would have been 11 14/33 because in the fractional form this is the reduced amount. As a mixed fraction that's as low as it will go.
Perhaps 11 42/99 is good teaching but 11 14/33 is good math.
