Which of the Following Scenarios Illustrates Concurrent Control

Which of the following scenarios illustrates concurrent control?

A) Susan, the customer care manager in an amusement park, actively seeks feedback from visiting tourists.
B) Jean, the manager in a restaurant, ensures that the vegetables used in cooking are organic.
C) Rebecca, the supervisor in a toy factory, gives suggestions to workers when they look for new designs.
D) Joshua, the stock manager in a steel factory, checks every evening whether adequate stocks are available for the next day's operations.