Logical ReasoningDifficulty: Medium

PT1 S4 Q16 Explanation

Professor: If both parents have type O

A free, expert breakdown of this official LSAT Logical Reasoning question.

TopicsFlaw

Keep going in LSAT Lab

  • Save & drill this skill — build targeted practice sets from questions like this one

  • Video walkthroughs — watch every question solved step by step

  • 81 official LSATs — as questions, timed sections & full-length tests

Start practicing free

Free to start

Full official LSAT questions are available through LawHub. This page provides LSAT Lab's explanation, strategy, and review tools without republishing the full official question.

Stimulus

Professor: If both parents have type O blood then their children can only have type O a genetic law.

Student: But that’s not true. My father has type B blood and I blood.

What this question is testing

Flaw

Your task

Describe the reasoning error the argument actually commits.

Common trap

Answers that name a real logical flaw the argument doesn't actually make.

Winning move

Articulate the gap in the reasoning yourself, then match it to the choice that describes that gap.

Reading along? Open the full official question in LawHub — we show a fragment here and keep the reasoning in our own words.

The question
16.

The student has most likely misinterpreted the professor’s remark to

Answer choices

  1. Correct80% picked this

    Only people with type O blood can have children with type

    Why this is right

    Answer A is correct.

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

  2. Trap10% picked this

    People with type O blood cannot have children with type

  3. Trap4% picked this

    People with type B blood invariably have children with type

  4. Trap1% picked this

    What is true of one child in the family must also be true of all

  5. Trap5% picked this

    If both parents have type B blood, then their child will have

Continue the review in LSAT Lab

Save this question, watch the video walkthrough, and drill similar questions in your LSAT Lab account.

Save and practice this skill
LSAT Lab

Turn this review into a targeted study plan.

Save this question, drill more like it, watch the video walkthrough, and track your progress in your LSAT Lab account.

Start practicing free