What is the advantage of the multithreading program?

(a) Enables to utilize the idle and executing time present in most programs

(b) Enables to utilize the idle time present in most programs

(c) Both Enables to utilize the idle and executing time present in most programs & Enables to utilize the idle time present in most programs

(d) Only Enables to utilize the idle time present in most programs

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This interesting question is from Multithreaded Programming in portion Reflections, Multithreaded Programming, Collection Classes and Mathematical Functions of C#