What sum is represented by the following number line?
A.) 2 3/4 +(-4 3/4) =-1 2/4
B.) 2 3/4 + (-4 1/4) = -1 2/4
C.) -1 1/2 + 2 3/4 = 4 1/4
D.) 2 3/4 + (-3 1/4) = -1 2/4
