The weights of 4 boxes are 30, 70, 60 and 20 kilograms. Which of the following cannot be the total weight, in kilograms, of any combination of these boxesÂ and in a combination a box can be used only once?

The weights of 4 boxes are 30, 70, 60 and 20 kilograms. Which of the f

1.	The weights of 4 boxes are 30, 70, 60 and 20 kilograms. Which of the following cannot be the total weight, in kilograms, of any combination of these boxesÂ and in a combination a box can be used only once?
A.	180
B.	190
C.	120
D.	150
Answer» C. 120