An object is marked for garbage collection once its reference count reaches zero. the correct answer is option(b).
A programming technique called reference counting counts the number of handles, pointers, or references to a resource, such as an object, a block of memory, disk space, or another one. Reference counts may be utilized in garbage collection algorithms to deallocate items that are no longer required. When there is no reference to an object in a program, it is deallocated as part of reference counting, a memory management technique.
The object is destroyed and the memory is released when the count is zero. When objects reference one another repeatedly, reference counting is invalid. Even though nothing references the cyclic structure in these situations, each object will be perceived as being referenced and will never be released.
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