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.
Depending on what trait the alleles carry, the brothers will have a different phenotype and a different genotype.
For example; Eye color. My sister is heterozygous, meaning she has brown eyes. I am homozygous recessive, meaning I have blue(green/hazel) eyes. We both have the same parents, I just happened to inherit both of the recessive eye color alleles from my parents whereas, my sister inherited both the dominant and recessive alleles.
So, since the brothers inherited different sets of alleles, their genotype for a certain trait will be different.
For the leaves to be presearved as fossil, they have to undergo a natural process of carbonization. This involves a slow chemical reaction with water over time that allows oxygen, nitrogen, and hydrogen to escape the leaves’ structure as gases leaving behind a carbon skeleton/film.
Answer ; A.) Aquatic Animals .
It’s the subsoil layer. Hope this helped :)