We can go by the definition of the word "repose" at first:
"a state of rest, sleep, or tranquility" or "be lying, situated, or kept in a particular place."
Even in the context, you can see nothing to support the idea of repose meaning energy, anger or light. Juliet is saying: "I hope you enjoy the same sweet peace and rest I feel in my heart."
The correct answer is: D)calm