Adynamic strength isa. safe, because it involves gradual and crontrolled movementsb. safe, because it extends the joint beyond its range of motion c. unsafe, because it uses the body's momentum to stretch the musclesd. unsafe, because it requires quickly stretching the muscle and joint

Which of the following processes within viral replication is the greatest source of genetic variation in rna virus populations? a) high mutation rate due to lack of proofreading of rna genome replication errors.b) transcription from the host cell rna polymerase introduces numerous mutations.c) capsid proteins from the host cell can replace the viral capsid.d) viral rna is translated by host cell ribosomes.