PrepTest 117 · Section 4 · Question 21 (Parallel Reasoning)

Step 1 · Pre-Question Guidance · read this first

Question type

Parallel Reasoning

The one idea it tests

An option is worse if a bad event happens, but it makes the bad event less likely, so it is recommended anyway.

The basic logic

Strip the argument to its skeleton: Option X gives less cushion when trouble hits. But X makes trouble less likely to hit. So choose X. The right match must have the same two-part trade: a downside that appears only after the bad event, outweighed by lowering the odds of that very same event.

Tiny words that decide it

“but”
“since”
“less likely”
“better”

Playground logic

Tommy admits his sock drawer protects candy worse than a lockbox if Lulu finds it. But Lulu almost never searches the boring sock drawer. So the drawer wins. The patty has two sides of the same event: worse when found, but less likely to be found.

Step 2 · The kid story

The Sock Drawer Strategy

Tommy sat on his bed with a chocolate bar and a big decision. 'Option one: the metal lockbox. If Lulu finds it, she still cannot open it. Option two: the sock drawer. If Lulu finds the candy there, it is gone. Totally unprotected.' Marcus nodded. 'Lockbox, obviously.' Tommy shook his head. 'Nope. A lockbox screams TREASURE. Lulu would hunt for it all week. But nobody searches a sock drawer. Socks are boring. So the sock drawer is better, because Lulu will probably never find it at all.' Priya tilted her head. 'Worse if she finds it, but much less likely she finds it. That is your whole argument.' From the hallway, Lulu wrote on her clipboard: 'Check sock drawer.' Biscuit was already sniffing it.

Step 3 · Try the model question

Tommy: Hiding candy in my sock drawer protects it less than a lockbox if Lulu finds it. But since nobody searches a boring sock drawer, the sock drawer is the better spot, because Lulu is less likely to find the candy at all.

Which argument follows reasoning most like Tommy's?

Step 4 · The courtroom tale

The Case of the Glass Bakery Door

A baker was sued by her landlord for swapping a steel door for a glass one. The landlord's lawyer stood. 'Glass breaks easily if a burglar tries it. Steel does not!' Mr. Whitfield rose, suspenders shining. 'True, Your Honor. If a burglar comes, glass protects less. But the baker's glass door lets the street lamp show every corner of the shop, and the night patrol can see inside. Burglars avoid shops where they can be seen. So break-ins become much less likely.' He spread his hands. 'Weaker when trouble comes, but trouble rarely comes. That is a fair trade.' The judge smiled. 'I will allow the door.'

Step 5 · Work the real question

Open PrepTest 117, Section 4, Question 21 in your official copy from LSAC (for example in LawHub) and read it there.

Your answer

How to apply it

Write the real argument as a skeleton: option, its downside once a bad event happens, its effect on how likely that same bad event is, and the recommendation. Then check each choice for all four pieces. Make sure the lowered odds apply to the same event that makes the option look worse. Choices that trade two unrelated features, or that lower harm after the event instead of its odds, are Broken Twins.