The correct answer here is certainly B. They allow scientists to perform new investigations and test new ideas they may not have been able to do in the past because scientists have been able to do the other 3 options without modern technology.
This definition above refers to the geographic isolation.
It means exactly what it says in the definition - one species is left behind from the rest of the population, and it stays in that particular location, evolving and changing from the species and population it was once a part of.
Answer:
During METAPHASE the chromosomes line up along the equatorial plate.
