Answer:
Egoism
Explanation:
According to my research on studies conducted by various sociologists, I can say that based on the information provided within the question Martha's behavior is a clear example of Egoism or Ethical Egoism Theory. This is a theory which describes a person's actions proving that moral agents act on behalf of the individuals own self-interest. Which is what Martha is doing by lying about her computer.
I hope this answered your question. If you have any more questions feel free to ask away at Brainly.