Instruction 2-2
at a Meeting of Information Systems Officers for Regional

Instruction 2-2
At a meeting of information systems officers for regional offices of a national company,a survey was taken to determine the number of employees the officers supervise in the operation of their departments,where X is the number of employees overseen by each information systems officer.
$$\begin{array} { l r } X & f \\\hline \hline 1 & 7 \\2 & 5 \\3 & 11 \\4 & 8 \\5 & 9\end{array}$$
-Referring to Instruction 2-2,how many regional offices are represented in the survey results?

A) 11
B) 5
C) 15
D) 40