Final answer:
The answer is option 4) Both a and b are correct. Two competing species can avoid competition by excluding each other from the habitat or working together in a mutualistic way. They can also segregate niche using narrower parts of the niche they would use if they were alone to reduce competition.
Step-by-step explanation:
The answer to your question is option 4) Both a and b are correct.
In order to avoid competition, two competing species can either exclude each other from the habitat (option a) or work together in a mutualistic way (option b). Exclusion occurs when one species is able to outcompete the other and drive it to extinction, while mutualism involves a cooperative relationship between the species.
However, it is important to note that there is another way in which species can avoid competition, which is option 3) segregating niche using narrower part of the niche they would use if they were alone. This means that the species can partition their niche into narrower subsets, using only a specific part of the resources available in the habitat. By doing so, they reduce direct competition with each other.