C. By explaining how the Dinomatron toy is different from last year's popular toy.
Explanation:
The author would best respond to the counterclaim that Dinomatron is made by the same company that created a holiday toy shortage the previous year by explaining how the Dinomatron toy is different from last year's popular toy. The author's counterclaim will show that there Dimantron is unique and different and could not compared to the previous year's popular toy. Dinomatron brand of toys has distinguishing features that makes it unique from others.
