Question 1171325
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Answer: B. Affirming the conclusion; not valid


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We affirm the conclusion because the conclusion is "you must use an oven". Specifically the sentence "Jessica used an oven" is the affirmation. 


However, this is not valid because the conditional does not go both directions unless we're talking about a biconditional argument. In this case, we have single direction conditional. The hypothesis must be true to lead to the conclusion, and not the other way around. There may be other ways to reach the conclusion. 


So in short, the fact that Jessica used an oven does not mean she baked bread. She could have baked pizza or some other kind of food.
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