Biologists Tell Us That Life on Earth Took Billions of Years

Multiple Choice

Biologists tell us that life on Earth took billions of years to evolve into astronomy students and other examples of intelligent life. If we want to search for planets with intelligent life-forms that evolved over the same period of time that we did, what sorts of stars should we not bother searching around?

A) relatively low-mass main sequence stars
B) O and B type stars
C) G type stars
D) main sequence stars with surface temperatures of about 6,000 ^oK
E) all stars live such a long time that life as we know it can evolve around them even if it takes billions of years