Context: Ariadne also notices that her crystal pendant , the one given to her by the girl , Serena , is vibrating and glowing slightly . The girls told her that the crystal was " sensitive to spirits " . As the party ascended the stairs , the pendant only grew brighter , indicating a high level of spirit activity . At the top of the stairs they found what remained of a once - lavishly appointed bedchamber .

Question: What 's a possible reason the crystal pendant is vibrating and glowing ?
Options:
0. Because it was given to Ariadne .
1. Because it was given by Serena .
2. Because it has magical properties .
3. None of the above choices .
Answer: 2