Viruses can have beneficial effects.

Answer choices

1. A

   Compatible13% picked this

   Random mutation makes some deadly viruses beneficial

   We hear that random mutation could switch a few atoms and turn a beneficial virus into something deadly. It seems like random mutation could switch a few atoms and turn a deadly virus into a beneficial one. We certainly can't contradict this. We would need proof that "random mutation can never turn a deadly virus into a beneficial one".

   13%
2. B

   Compatible9% picked this

   Some organisms of greater complexity than viruses are no more likely than viruses to undergo significant

   This is saying that an organism of greater complexity than a virus may be less likely to undergo a significant alteration through mutation. That seems very possible, if not likely. Contradicting this answer would mean that in the passage we learned that "every organism of greater complexity than a virus is more likely than a virus to undergo significant alternations through mutation". We certainly were provided with no information that we could apply to "every organism of greater complexity than a virus".

   9%
3. C

   Compatible4% picked this

   Some microorganisms that are more complex than viruses are beneficial

   It's certainly possible that there is at least one microorganism more complex than a virus that is beneficial to humans. To contradict this, we would have needed to have been told that "all microorganisms that are more complex than a virus are either neutral or damaging to humans".

   4%
4. D

   Out of Scope: virus killing virus8% picked this

   Some viruses that fail to kill other viruses that are deadly to humans are nevertheless

   We don't have any information at all on the subject of this sentence (viruses that fail to kill other viruses), so we can't contradict it. To contradict this, we would have needed to have been told that "every virus that fails to kill a virus that's deadly to humans is either neutral or damaging to humans".

   8%
5. E

   Correct66% picked this

   No virus that is deadly to organisms of greater complexity than itself is

   Why this is right

   All four of the other answers had weak, watered-down "some" language. Those are scary answers on Must Be False, because to contradict "some" you need to prove "none". As we considered each of those four answers, we thought about how extreme the contradiction idea would be. Here, they're giving us an extreme idea, which is much easier to contradict, because you only need one exception to do so. If someone says "No men like ballet", you only need one man who likes ballet to contradict that. Since this says, "No virus that's deadly to more-complex organisms is beneficial to humans", we can contradict it if we have one example of a virus that's deadly to more-complex organisms that is also beneficial to humans. The first two sentences give us that. Some viruses kill more-complex organisms (they are deadly to organisms of greater complexity than themselves) and are beneficial to humans.

   Skill tested: Must be False · how this choice captures the argument's function is the move to repeat next time.

   66%