The small ribosomal rRNA gene sequences of hyperthermophilic Archaea and Bacteria have relatively high GC content, which

A) increased stability at high temperatures because GC pairs are joined by 3 hydrogen bonds.
B) decreased stability at high temperatures because GC pairs are joined by 2 hydrogen bonds.
C) increased mutation rates at high temperatures compared with other rRNA.
D) considerable variation in their GC content, making this unhelpful as a distinguishing feature between them and non-hyperthermophilic Archaea and Bacteria.