Answer Options

@BrookeMag, I would just start with (A) and go down. Historically, each answer choice is the correct answer choice about 20% of the time, so starting with (E) confers no benefit. Thus, just start with (A) and go from there to keep things simple. Now, let's take a look at the question. We can diagram the stimulus: normal full-term babies - >disappeared reflexes reflexes didn't disappear - >not normal full-term baby This argument is using the contrapositive of the original statement to conclude that the baby isn't a normal full-term baby. This is a valid argument structure. If A, then B not B, therefore not A (D) says, "Because opossums have abdominal pouches and this animal lacks any such pouch, this animal is not an opossum." This can be diagrammed as O - AP /AP - >/O This argument matches the contrapositive format of the one in the stimulus, so it's the correct answer choice. Does this make sense?

Yes got it, thank you!

@BrookeMag, you're welcome!