I would have to say probably d.
Answer:
increasing[1], higher[2], space[3], food[4], climate change[5].
Explanation:
Because global temperatures are <u>increasing[1]</u>, some species are seeking out <u>higher[2]</u> elevations in the Himalayas to colonize. Scientists were worried that these organisms would not have enough <u>space[3]</u> to live, but they have found that there is adequate <u>food[4]</u> at higher elevations. This movement may help these organisms survive the effects of <u>climate change[5].</u>
(Although am positive about 1, 2 and 5, you will need to double check 3 and 4. What I can tell you is that I don't think lifespan has to do with 3 or 4. I chose space and food simply due to the thought that more species moving to higher elevations allows for less space to live, but more prey to be hunted easier.)
Molecular clocks use rates of mutation to measure evolutionary time.Mutations add up at a fairly constant rate in the DNA of species that evolved from a common ancestor. The more mutations that happened in each lineage, the greater is the differences between these lineages.
