Controllers are required to perform which of the following tasks effectively?

The correct choice emphasizes the critical communication skills necessary for effective air traffic control. Speaking clearly is vital as controllers must issue instructions and information to pilots accurately. Hearing is equally important, allowing controllers to understand pilot communications, including acknowledgments and requests. The ability to remember information is crucial since controllers often need to retain and apply various data points, such as flight plans, traffic situations, and instructions given to different aircraft, all of which is necessary for maintaining safety and efficiency in the airspace.

The other options, while containing some relevant skills, do not encompass the specific combination of speaking, hearing, and remembering that is fundamental to the role of a controller. Analyzing and reacting might be essential skills in certain contexts, but without speaking and hearing, effective communication would falter, as would the controller's ability to manage air traffic effectively.