A researcher recently discovered a new species of bacteria in the body of a tubeworm living near a hydrothermal vent. He compared the DNA of this new bacterial species to the DNA of four other species of bacteria. The DNA sequences came from the same part of the bacterial chromosome of all four species. According to these data, the unknown bacterial species is most closely related to

That are more similar to each other.

Explanation:

The unknown bacterial species is most closely related to that bacteria which experience high temperature because both bacteria can live and survive in hot climatic conditions. The new species of bacteria and other four bacteria have some similar features due to similar chromosome but also have some differences due to difference in environmental conditions where they survived so those bacteria that have more similarities are more closely related to each other.

did you fail the test? xd

correct answer is a. and d.