Chemical analysis of the DNA of a virus from Mars reveals that it has 48% A, 48% T, and 4% G, Suggest some possible structures for this DNA.

Question

I don't quite understand this question. All i can come to think about is that A pairs with T evenly because of the percentages, making it 96% and there will be G leaving out to pair themselves because of the 4%, adding them all together it will be 100%. Is this the answer they want? or is it asking something completely different?