Which statement is scientifically based? mutations rarely occur. all mutations are harmful. some mutations can be contagious, like infections. mutations are not passed from parent to offspring.

The correct answer would be "Mutations rarely occur".

A mutation is a rare event during which the gene or DNA is changed or damaged.

For example, the mutation rate during DNA replication is around one in 10 billion base pairs.

It can be caused either by environmental factors such as UV radiations or any other mutagens (either chemicals or radiations) or due to errors during DNA replication.

Not all mutations are harmful, most of the mutations are neutral in nature, that is, they are neither beneficial nor harmful. In addition, few mutations may add a survival advantage to the population.

Mutations are not contagious like an infection.  

They are passed from parents to the offspring only when they take place in germ cells.

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