I've included my code in the picture below. Best of luck. 
 
        
             
        
        
        
Answer:
A real-time operating system is an operating system designed to support real-time applications that, usually without buffer delays, process data as it comes in. A real-time system is a time-bound system that has fixed, well defined time constraints.
 
        
             
        
        
        
Answer:
Option (D) i.e., Parallel start up is correct option to the following question.
Explanation:
Parallel startup is also an application or software or a way of using the application of the other Operating System in others just like that the following XYZ inc. has trust on older platform but their system give them cautions for update then they use parallel set up by which they also use old software, as well as they, use the Mac's software in Windows. This strategy provides both the option of usage.
 
        
             
        
        
        
Answer:
huge\color{blue}\boxed{The}\huge\color{pink}\boxed{Points
 
        
                    
             
        
        
        
electro-mechanical data storage device