Final answer:
Guanylate-Cytosine (G-C) base pairs have stronger base stacking interactions due to the presence of three hydrogen bonds, compared to the two hydrogen bonds found in Adenine-Thymine (A-T) pairs.
Step-by-step explanation:
The student has asked which base pairs have stronger base stacking interactions. Within DNA, base pairs are composed of a purine and a pyrimidine. The base pairs Guanylate-Cytosine (G-C) is known to have stronger base stacking interactions. This is due to the fact that G-C pairs form three hydrogen bonds between them, as opposed to Adenine-Thymine (A-T) pairs, which only form two hydrogen bonds. Because each G-C base pair has an additional hydrogen bond compared to A-T pairs, the G-C interactions are stronger, contributing to the stability of the DNA helix structure. Options such as Adenine-Uracil (A-U) and Thymine-Cytosine (T-C) are not standard base pairs found in DNA, with A-U only occurring in RNA and T-C not forming a complementary base pair under normal conditions.