Answer:
B). Stability.
Explanation:
The description given provides that the disagreement between Marta and Isabelle exemplify that they are elaborating the 'stability' in Greta's behavior. 'Stability' is the attribute that is associated to the condition of being resistant to change and state of remaining sound. Marta's point provides a selfish and arrogant characteristic to Greta while Isabelle's point contradicts this and establishes her 'stability' by stating that such a behavior is occasional as an outcome of 'getting very little sleep'. This proves that Greta is stable and sound in her behavior and coherent in her thoughts. Therefore, option B is the correct answer.