The phenotype of an organism that is most commonly observed in nature is called the

Wild type

Explanation:

It refers to the phenotype that is found in nature. Naturally the form that is commonly seen in nature and is used for experiment is this type only.

This concept is useful in many experiment as it can be used as a model organism. Example: Drosophila melanogaster.

Manipulation of genes produces different type of phenotype other than wild type which is not generally seen in the nature.

the correct answer is b

answers are:

lysogenic     viral dna merges with host cell dna

lysogenic     no symptoms

lytic               viral dna takes over

lysogenic     virus does not destroy host cell

lytic               virus destroys host cell

lytic               induces symptoms of viral infection

lysogenic       cell reproduces and spreads provirus