When individuals improve their aerobic endurance, which body systems are affected? A
digestive and muscular

B
circulatory and digestive

C
respiratory and digestive

D
circulatory and respiratory

PLEASE HURRY FINAL EXAMS

Why do rna viruses appear to have higher rates of mutation? a) rna nucleotides are more unstable than dna nucleotides.b) replication of their genomes does not involve proofreading.c) rna viruses can incorporate a variety of nonstandard bases.d) rna viruses are more sensitive to mutagens.