There were no choices provided. But there is a related research about this situation.
Risk factors of influenza transmission in households
Source: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1326070/
<span>>Reasons for increased transmission from children
</span> The research pointed three causes.
1. Children are more exposed to different people in different places. their households, peers in schools and other children.
2. Children especially preschools are said to have lower immunity which makes them prone and catching influenza.
3. Lastly, viral shedding among children can alleviate and spread period of infection.
B. an ecosystem
An ecosystem contains a community (several species of organisms) and the environment including air, water, and more.
Answer:
A
Explanation:
Cardiovascular diseases involves the heart.
Any of the above options with regards to blood (etc, white blood cells, red blood cells) are related to circulatory system, not affecting the function of the heart.
Stem cells performing apoptosis to remove old cells is a myth. Stem cells can only differentiate to form cells of the same lineage, not causing other cells to undergo apoptosis. The only external factor that can cause cells to undergo apoptosis is a type lymphocyte in the immune system
