Logical Reasoning

PT129 · S3 · Q24 It is widely believed

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It is widely believed that lancelets—small, primitive sea animals—do not have hearts.

Evidence

It strongly resembles the RSH structure of the heart of certain other sea animals.

The muscular contractions RCH in the lancelet's vessel closely resemble the muscular contractions of other animals' hearts.

Conclusion

This vessel is indeed a H heart.

Evaluate

The argument assumes RSH + RCH → H that if a vessel has the structure of a heart and has contractions that resemble a those of a heart, then that vessel is a heart.

24.

The argument's conclusion follows logically if which one of the following is assumed?

  1. Only animals that have contracting

    Reversal

    This answer reverses H → RCH the connection between muscular contractions and being a heart.

    2% picked this

  2. Some primitive animals other than

    Out of Scope

    Primitive animals other than lancelets are out of scope for this argument since it is unknown whether there is any similarity between their hearts and the lancelet’s vessel.

    1% picked this

  3. Correct

    A vessel whose structure and

    Why this is right

    This bridges the gap RSH + RCH → H between a vessel that resembles the structure and actions of a heart and a vessel that is a heart.

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

    88% picked this

  4. For a vessel in an

    Reversal

    This answer reverses H → RCH the connection between muscular contractions and a vessel being a heart.

    8% picked this

  5. No animal that has a

    Out of Scope

    The relationship between H → A having a heart and having an artery is irrelevant to the argument.

    1% picked this

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