Read the following context and choose the best option to answer the question.
Context: Yamapi exclaims and bows again . They talk a bit more about the DVD and Yamapi says thanks again and then they part ways . Everyone in the room found it odd that Yamapi has n't spoken at all and the meeting was already halfway through . He was also wearing this really odd bonnet .
Question: Why are some unnerved by Yamapi 's behavior ?
Options: 
- They are unnerved by his lack of speaking .
 - They are unnerved by him selling DVDs .
 - They are unnerved by him being on the DVD .
 - They are unnerved by him destroying the DVDs .


They are unnerved by his lack of speaking .