LIFE SCIENCE

Detailed explanation-1: -Viruses can only replicate in living cells. For studies of the growth of viruses and for the production of virus components it is therefore necessary to have access to cells cultivated in the laboratory.

Detailed explanation-2: -Viruses need to be inside a living cell (a host) to live and grow. Viruses are like photocopiers, they can make lots of copies of themselves once they are inside a host.

Detailed explanation-3: -So, the correct option is B. ( Living host )

Detailed explanation-4: -Although viruses are not classified as living things, they share two important traits with living things. They have genetic material, and they can evolve.

Detailed explanation-5: -Viruses manipulate host cells into building new viruses which means each virion is created in its fully-formed state, and will neither increase in size nor in complexity throughout its existence. Viruses do not grow.