Question

A is true because a constant (which can be of any value ) is involved when you do the 'anti-derivative'  

 

   Example  Anti derivative   x²  +3             x^2 +12            x^2 +19 

                 all have derivative    of   2x  

                        so, in other words , the 'anti-derivative' of   2x     can be     any of the red equations (or more)