In Swartkans territory, archaeologists discovered charred bone fragmen

We are trying to strengthen "the claim that the charred bone fragments are evidence of the use of fire by early hominids".

Pay close attention to the wording of the question stem, though! We are not just trying to show that early hominids used fire. We are trying to show that the charred bone fragments ARE EVIDENCE that early hominids used fire. That's a very subtle distinction, so make sure that is clear before you proceed to analyze the argument:

• Archaeologists have discovered 1-million-year-old charred bone fragments in Swartkans territory.
• The bone fragments came from a variety of animals.
• The bone fragments "had been heated to temperatures no higher than those produced in experimental campfires made from branches of white stinkwood." Notice the use of "no higher than". That means that it is POSSIBLE that all of the bones were exposed to campfires made from white stinkwood branches. This does not PROVE that the bones were exposed to white stinkwood campfires, but it tells us that this is a possibility.
• White stinkwood is "the most common tree around Swartkans."

So far, the evidence could support that campfires made from white stinkwood branches were used to cook animals in Swartkans one million years ago. We need an answer choice that supports the idea that the charred bone fragments are in fact evidence of the use of fire by early hominids. Again, we are not simply trying to show that early hominids used fire. We are trying to show that the million-year-old charred bone fragments are evidence that they used fire.


We don't care whether white stinkwood is or was used for building material. We are trying to show that white stinkwood campfires were used to cook animals in Swartkans a million years ago. Choice (A) is not relevant to this claim and can be eliminated.


If this is true, then the bones might have been charred by forest fires and not by campfires. This would actually weaken the argument, so eliminate (B).


Even if they could not fit the bones together, we would still know that we are dealing with charred animal bones. We are trying to figure out whether those animal bones were charred by campfires. Whether scientists can piece the bones back together has no bearing on the claim, so eliminate (C).


This one sounds great! We have evidence that early hominids used fire! That's what we were trying to show, right? Nope! We are trying to show that the million-year-old charred bone fragments are evidence that they used fire. If you didn't read the question stem carefully, you likely chose this tempting answer. But this does not tell us anything about whether those bones were charred by early hominids who built campfires. (D) only tells us that early hominids used fire up to 500 thousand years ago. Maybe early hominids used fire a million years ago, but choice (D) doesn't even support that claim. (D) must be eliminated.


All we have so far is a bunch of charred animal bones. Theoretically, they could have been charred by white stinkwood campfires. But who's to say that there were even any early hominids around to make such campfires? Right now we have no connection between the early hominids and the charred bones. All we know is that it is POSSIBLE that the bones were charred by white stinkwood campfires in Swartkans and thus that it is POSSIBLE that early hominids made those campfires in Swartkans. But it is still just as possible that the bones were charred some other way (i.e. forest fires). We don't have any strong evidence that early hominids were even around.

Choice (E) provides strong evidence that early hominids were around when the bones were charred. This does not PROVE that early hominids charred the bones with campfires, but it certainly strengthens this theory. Now what do we know: a million years ago in Swartkans we likely had early hominids AND charred animals bones AND trees that could have been used to make fires that charred those bones. Choice (E) supports the claim that the charred bones ARE evidence that early hominids used fire.

(E) is the best answer.