The correct option is
B Let's discuss all the options one by one:
Option (a).
In this graph, salary per month increases with time, which is not the given scenario.
Option (b).
In this graph, salary per month remains constant with time.
Hence, This best represents the given scenario.
Option(c).
In this graph, salary per month decreases with time, which is not the given scenario.
(d).
In this graph, salary per month increases with time, but again it started decreasing, which is not the given scenario.
Hence, option (b.) is the correct one.