Which piece of information in the text is LEAST relevant?

A.
The system was based on earlier work that the researchers used related to the flu and the influences of lifestyle choices on people’s health.

B.
Public health officials could spend their limited time and money inspecting restaurants that are most likely to be problematic.

C.
If a person's tweets show they are suffering from a foodborne illness, the system then traces back their steps to find the restaurant most likely to be the source.

D.
Over four months, the researchers examined 3.8 million tweets from 94,000 people living in New York City.