It would be A
First is: DNA > mRNA (messenger RNA) > tRNA (transfer RNA) > protein
All the options are correct.
1. New ways to preserve and transport blood for blood transfusions were discovered.
2. Blood transfusion safety was improved.
3. Scientists discovered that elements of blood could be separated by centrifuge.
4. Scientists discovered that plasma could be preserved by freezing.
Karl Landsteiner
Karl Landsteiner was the man who discovered some of the human blood types in 1900 and 1901 at the University of Vienna.
Answer:
Prezygotic barriers:
1. Habitat isolation
2. Behavioral isolation
Explanation:
Pre-zygotic barriers are the barriers which do not allow the formation of the zygote in the organisms.
The two mechanisms of the pre-zygotic barriers are the:
1. Habitat isolation: the Flycatchers do not share the same habitat which is also mentioned in the question that they live on different islands.
2. The behavioural isolation: the Flycatchers could have evolved the different mating rituals as a result of which the could not interbreed.
Thus, Habitat isolation and Behavioral isolation are correct.
Answer: I would say the answer is D. ( my opinion )