#25 - If squirrels eat from a bird feeder, it will not

[Administrator]

Complete Question Explanation

Parallel Flaw. The correct answer choice is (B)

This stimulus is a collection of conditional reasoning statements, from which the author draws a questionable conclusion. First, the author provides that when a squirrel visits a bird feeder, the feeder attracts less birds:

• Squirrels eat from feeder feeder attracts less birds

Next, the author provides that the only time squirrels eat from a bird feeder is when the feeders don’t have a protective cover:

• Squirrels eat from feeder protective cover

Since the two conditional statements contain the same sufficient condition, they can be joined as follows:

• Feeder attracts less birds
  Squirrels eat from feeder +
  protective cover

The author then draws the flawed conclusion that any feeder without a protective cover will attract less birds. Basically the author takes two necessary conditions and draws a flawed conclusion on their basis:

• Protective cover Feeder will attract less birds

The author mistakenly believes that the lack of a protective cover will guarantee that squirrels eat from a bird feeder. This is a mistaken reversal of the second conditional statement in the stimulus.

The question is followed by a Parallel Flaw question, so the correct answer choice will likely provide two conditional statements, and link two necessary conditions to draw a flawed conclusion.

Answer choice (A): The reasoning here is somewhat different from that found in the stimulus. The author begins with two conditional statements that almost create a double-arrow.

If tire pressure is too low, it will wear out prematurely:

• Tire pressure too low wear out prematurely

…and if a tire wears out prematurely, low pressure is a likely cause

• Wear out prematurely low pressure a likely cause

The author then introduces an entirely new condition to the flawed conclusion:

Therefore, if an owner checks the tires regularly, the tires won’t wear out early:

• Owner checks pressure regularly Tires will wear out prematurely

This is certainly a flawed conclusion, but because it does not mirror the flawed reasoning in the stimulus, it can be ruled out as a contender.

Answer choice (B): This is the correct answer choice. Like the stimulus, this choice provides two conditional statements, followed by a flawed conclusion linking the necessary conditions. If the air pressure is too low, a tire will wear out early:

• Air pressure too low premature wear

The air pressure will be too low only in cases when the owner doesn’t perform regular pressure checks:

• Air pressure too low fail to check pressure regularly

Again, as with the stimulus, the two conditional statements can be linked as follows:

• premature wear
  Air pressure too low +
  fail to check pressure regularly

From here, the author uses the two necessary conditions to draw the flawed conclusion that failure to check air pressure regularly will cause a tire to wear out prematurely:

• Fail to check pressure regularly premature wear

Since this flawed line of reasoning perfectly parallels the flawed reasoning found in the stimulus, this choice is confirmed to be the right answer.

Answer choice (C): This choice begins much like the others, with a straightforward conditional statement: If car owners don’t check their tire pressure regularly, their tires can wear out early:

• regular pressure checks wear out prematurely

This answer choice then proceeds with a somewhat tricky “unless” statement: unless car owners are unaware, they check their tire pressure regularly. We can diagram this statement by using the Unless Equation:

• regular tire press checks owners unaware
  
  And the contrapositive: Owners aware regular tire pressure checks

The author then concludes by stating that owners must be made aware of what can happen if they don’t perform regular tire pressure checks.

This line of reasoning is very different from that found in the stimulus; in particular, the conclusion here is not flawed, so there is no way that this choice can parallel the flawed reasoning found in the stimulus.

Answer choice (D): This incorrect answer choice starts out in the right direction, but then goes off course with valid reasoning. The first conditional statement is that if the pressure in a tire is too low, it will wear out prematurely:

• Pressure too low wear out prematurely

Unlike the stimulus, which follows up with an “only if” statement, this choice proceed with an “if” statement: This is a vital distinction, as we can see from the diagram:

If the owner fails to check the pressure regularly, tire pressure will become too low:

• Fails to check pressure regularly pressure too low

A linking of the two conditional statements from this answer choice together produces the following conditional chain:

• Fails to check pressure regularly pressure too low wear out prematurely

The conclusion in this answer choice is that if an owner fails to check the tire pressure regularly, the tires will wear out prematurely. This conclusion is a valid one, confirmed by the conditional reasoning chain above. Thus, this answer cannot possibly parallel the flawed reasoning from the stimulus.

Answer choice (E): Rather than following the line of reasoning from the stimulus, this choice presents a flaw of a different sort.