In the past, most children who went sledding in the winter snow in Ver

Since we are looking for an answer choice that most undermines the force of the evidence cited, let's start by identifying that evidence: "the number of children injured while sledding was much higher last winter than it was ten years ago."

According to the author, this evidence "clearly" leads to the concern that plastic sleds, which became more popular ten years ago, are more dangerous than wooden sleds. To recap the author's argument:

• Wooden sleds, with runners and steering bars, were used in the past.
• Ten years ago, plastic sleds became popular.
• Plastic sleds are faster, harder to steer, and harder to slow down.
• "The number of children injured while sledding was much higher last winter than it was ten years ago." Remember that ten years ago plastic sleds had just become popular, so it is likely that wooden sleds were still prevalent as well (it's possible to have more than one popular option). But we can infer that plastic sleds are probably more popular now than they were ten years ago.
• The evidence in the last bullet clearly leads to the concern that plastic sleds are more dangerous than wooden sleds.

Now let's look for the answer choice that most undermines the force of the evidence cited:

Again, the evidence cited is "that the number of children injured while sledding was much higher last winter than it was ten years ago." This evidence seems to suggest that plastic sleds are more dangerous than wooden sleds. Even if a few children still use traditional wooden sleds, if injuries have increased since plastic sleds became popular, this still seems to suggest that plastic sleds are more dangerous.

The evidence cited does not require that ALL children use plastic sleds, so (A) can be eliminated.

This statement might explain why sledding is dangerous regardless of the type of sled. However, it doesn't give us any reason to suspect that plastic sleds are safer than wooden sleds or vice versa. Thus, choice (B) has no impact on the evidence cited and can be eliminated.

Imagine that plastic sleds and wooden sleds were both equally safe. But if plastic sleds can be used in a much wider variety of snow conditions, then children last winter might have simply gone sledding more times, on average, than children ten years ago. In other words, the odds of getting injured while riding a plastic sled could be the same as the odds of getting injured while riding a wooden sled. But if you can go sledding more times with a plastic sled, then you will have more opportunities to injure yourself.

Answer choice (C) provides an alternative explanation for the evidence, and this explanation does not require that plastic sleds are more dangerous than wooden sleds. So (C) undermines the force of the evidence cited. Keep this one.

As with choice (B), this is a general statement that presumably applies to sledding with both wooden and plastic sleds. It has no bearing on the evidence and can be eliminated.

We are GIVEN the fact that "the number of children injured while sledding was much higher last winter than it was ten years ago." Maybe there are more injuries per accident with wooden sleds, but this does not change the fact that, overall, there were more injuries last winter than there were when wooden sleds were more prevalent. We are not trying to change the evidence; rather, we are trying to undermine the force of the evidence. Choice (E) has no impact on the evidence and can be eliminated.

Choice (C) is the best answer.