Answer:
A. Free-living spirochetes will need to synthesize proteins to obtain or create their own food from the environment around them. Parasitic spirochetes can leech food particles from the animal host, and may not need to move towards those food particles.
Step-by-step explanation:
Spirochetes can be free-living aerobic or facultative aerobic species that are found in sulfur-rich fresh and marine water. Some other species of spirochetes are symbiotic or parasitic and are mainly found in hindguts of termites and digestive systems of mollusks and mammals.
The spirochetes species living in the bodies of other organisms obtain their nutrition from the host and do not require the proteins involved in various steps of nutrition.
On the other hand, free-living spirochetes require the proteins involved in the process of nutrition and related activities. Therefore, the genome size of the free living spirochetes is larger than the one found in the bodies of the other organisms