Which is the world's only island city-state?

a. Singapore

b. Brunei

c. Malta

d. Bahrain

ANSWER: Singapore

Explanation:

A city-state is a sovereign state that consists of a city and its dependent territories.

Historically, this included famous cities like Rome, Athens, Carthage, etc.

However, a great deal of consensus exists that the term properly applies to Singapore, Monaco, and Vatican City. In particular, Singapore has been referred to by The Economist as the "world's only fully-functioning city-state".