Answer:
Chilmark .
Step-by-step explanation:
People moving into Chilmark area of Martha's Vineyard was required to learn sign language in order to live in their community.
This was because the number of deaf people living in the area of Martha's Vineyard was so high that the community made it necessary for everyone who lived in Chilmark to learn sign language.
This step made it easier for the deaf people to communicate with the rest of the residents more efficiently and easily.