When Emmett began his science experiment, he has 20 millimeters of an unknown solution. During the experiment, the change in the volume of the solution was -9 milliliters. What was his final volume of the solution. To solve the problem, dakota added 20+( -9 ) and came up with an answer of -11 milliliters. Is Dakota correct? Why or why not ?

A : yes, dakota is correct

B: No. The answer should have been 11 milliliters, not -11 milliliters, because the volume should not be negative

C: No. Dakota should have subtracted 20 - (-9) because the volume decreased