What Is the Most Plausible Explanation for Why Lost Items

What is the most plausible explanation for why lost items are recovered much more often in Tokyo than in New York City?

A) Japanese city dwellers are, on average, more honest than American city dwellers.
B) Japanese society is collectivistic, which means they are more helpful.
C) Tokyo has a well-established lost-and-found system, and New York City does not.
D) Options a, b, and c are equally plausible.