Ans: A
I is false. The number of cars sold for Brand $B$ is $40$ and that for Brand $C$ is $60$. Therefore, the number of cars sold for Brand $C$ is not two times that for Brand $B$.
I is false. The number of cars sold for Brand $B$ is $40$ and that for Brand $C$ is $60$. Therefore, the number of cars sold for Brand $C$ is not two times that for Brand $B$.
II is false. The number of cars sold for Brand $A$ is $30$. Then the total number of cars sold for Brand $A$ and $B$ is $70$, which is more than that for Brand $C$.
III is true. The number of cars sold for Brand $A$ is $30$ while that for Brand $C$ is $60$. Therefore, the number of cars sold for Brand $A$ is $50\%$ less than that for Brand $C$.
