I believe the term for two similar chromosomes would be homologous chromosomes.
Answer - Theory
Reasoning - Your best bet and term to describe the evolution by natural selection is theory as to still scientific theory/research is still ongoing and changes can be made in a different direction.
In science a hypothesis is useful only if...
1: it could be tested
2: their are two separate group
3: it's supported by evidence and facts
Answer: The liver
Explanation:
The liver produces a digestive juice called bile. The gallbladder stores bile between meals. When a person eats, the gallbladder squeezes bile through the bile ducts, which connect the gallbladder and liver to the small intestine.
:)