How many people averaged fewer than 4,000 steps each day?

a 7

b 10

c 19

d 21

The provided information does not specify the number of people and their respective step counts. Therefore, it is not possible to determine the answer to this question. Additional information is needed.

To determine how many people averaged fewer than 4,000 steps each day, we need more information about the data or the context of the question.