The ratio of the pumpkin to the cabbage is 3.2 to 1, written as 3.2:1.
3.2 + 1 = 4.2
Divide total mass by the sum of the ratios:
3.99 kg / 4.2 = 0.95
This means for every 1 ratio, the weight is 0.95 kg.
The pumpkin is 3.2 times, so 3.2 x 0.95 = 3.04 kg total.
This means the cabbage is 3.99 - 3.04 = 0.95 kg.
The difference in mass is 3.04 - 0.95 = 2.09.
The answer is A.