Viruses need to be inside a living thing (of course the living thing has to have the right temperature which most living things do) . When they're inside a living thing they start injecting the host's cells with its DNA in order to make more copies of itself which allows the virus to spread. So basically viruses need to be inside something living.
Answer:
The correct answer will be option-C
Explanation:
Lead is a metal found in the Earth's crust which through human practices like using it in paints and other products cause lead poisoning in humans due to accumulation of lead in the body.
Lead poisoning can affect the child above 6 years and adults and prove harmful as its increased concentration can cause severe health problems common of which are the development of anaemia due to large consumption, brain damage, reduced mental growth and severe stomach ache.
Thus, Option-C is the correct answer.
Answer:
The stimuli is photoreceptor
Explanation:
The fish has been conditioned to react to light so it has conditioned response