Scientists discovered a virus whose nucleic acid contained 25% adenine, 24% guanine, 28% thymine

Scientists discovered a virus whose nucleic acid contained 25% adenine, 24% guanine, 28% thymine and 23% cytosine. The hereditary substance of this virus is: 1) double-stranded DNA; 2) single-stranded DNA; 3) single-stranded RNA; 4) double stranded RNA

DNA is a two-helical nucleotide, RNA is one helical. In a DNA molecule, the adenine nucleotide is always complementary to thymine, that is, their number is the same. And the nucleotide cytosine is guanine. Since the number of nucleotides that make up the nucleic acid in the detected virus is not the same, it follows that the hereditary apparatus in the composition of this virus consists of an RNA molecule. And since an RNA molecule is a polynucleotide consisting of one strand (strand), then the answer is: single-stranded RNA.

Answer: point 3).