The correct answer is (B) Enclosed area; an area surrounded by foreign territory; territory belonging to one country or cultural or linguistic group, which is surrounded (or largely surrounded) by the territory of another country or group.

Enclave comes from French enclaver, Latin inclavare (to lock in) (in and clavis [key]).

Examples of use:

• The site of the Canadian Embassy is a tranquil enclave in the bustling city.
• Similarly, the west end of Montreal can be described as an English enclave within a sea of French language.