Motor oil serves to lubricate engines

Answer choices

1. A

   Opposite1% picked this

   Cheaper brands of motor oil are often used by knowledgeable automobile mechanics for

   This strengthens the argument, by saying that potential experts in the field of motor oil agree with the author.

   1%
2. B

   Too Weak8% picked this

   Tests other than of the ability to reduce engine wear also can reliably gauge the

   The key word also takes any punch out of this one. If the test we did was a reliable way to gauge the quality of motor oil, then it doesn’t matter that there are other reliable ways. Reliable ways will tend to all arrive at the same conclusion.

   8%
3. C

   Applies to Both4% picked this

   The lubricating properties of all motor oils deteriorate over time, and the rate of deterioration

   Since this fact applies to all motor oils, it is useless to our goal of highlighting some advantage of using the pricier motor oils.

   4%
4. D

   Unclear Impact / Too Weak6% picked this

   The engines of some individual cars that have had their oil changed every 3,000 miles, using only a certain brand of oil,

   This is too weak to be correct, as it applies to “at least one” individual car. But this answer also doesn’t specify whether we’re talking about a cheaper or pricier oil, so it’s impact is doomed to be unclear.

   6%
5. E

   Correct80% picked this

   Ability to retard engine wear is not the only property of motor oil important to the

   Why this is right

   If there are other important properties of motor oil besides retarding wear, then we can’t judge various brands of oil by looking only at how they retard wear. This opens the door for a line of objection such as, “Sure the cheaper brands are just as good at retarding engine wear. But the more expensive brands are better at doing X, which is also important to the running of an engine.”

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

   80%