PT1.S4.Q16 - Type O blood

moonstars5678

I know this is a very basic necessary/sufficient question but could someone validate the way I diagramed the logic?

Stim:
Professor: both O parents --> only O child
Student: not [both O parents --> only O child], but the student switched the professor's statement around to mean [only O child --> both O parents]. So given his logic, /both O parents --> /only O child (since he's Type .

ACs:
A) only O child --> both O parents
both O parents --> /type B child
C) both B parents --> only O children
D) irrelevant
E) both B parents --> type B children

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