To prove DEF ~ JKL by SAS, we would need to show that DE/JK = .

For SAS similarity, the two pairs of corresponding sides must be proportional, and the equal angle must be included between those sides. In triangle DEF, the sides around angle D are DE and DF; in triangle JKL, the corresponding sides around angle J are JK and JL. Thus DE/JK must equal DF/JL, which is choice A.

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