Answer:
they have short life spans and many predators.. hope this works
What is A B C and D? You have to tell us what the options are so we can answer.
Water, proteins, and ions as well as waste such as co2. It is often a straw color and it makes up about 50-60% of the total blood volume
The question must refer to the modern classification system in biology.
It started with the work of Linnaeus - so its early version can be called a Linnaean classification - but right now it has been expanded and changed to fit the evolutionary relationships between the species - which is the best description, i.e. the answer is "it is based on the evolutionary relationship of the species"
