While conducting a lecture on the types of operating system, Mohit's instructor asked him to name an opearting system that is used when the time span required to react to an input is rigid and time bound. Can you help Mohit in answering the question?

In a quiz competition, the quiz master asked one of the participants, Nyra, "In which user interface, the user mostly gets immediate visual feedback of the action he performs?" To this Nyra replied "CUI". Is she right? If not, what is the right answer?