GMAT Critical Reasoning (CR) | Automobile Dealers Advertisement: The Highway Traffic

I am confused over the second option. Option B says that the in recent years many more PZ 1000's have been sold than any other kind of car in its class. If the number of cars sold is very large, then average number of accidents per car[ total accidents/ total no of cars] would be low. This means that average number of injuries per accident for all the PZ cars would be low. So, can't we say that this option also weakens the argument? Since average number of low accidents is just because of large