When a copyright for a work has expired, the work is then said to be in the
a.
"shareware stage"
b.
private realm
c.
dustbin
d.
public domain

d)public domain

Explanation:Copyright is the right or the permission that is provided to an individual for using any service or application. When the copyright expires then there is no more permission to use the service by the user. In this case the work is shifted to the public domain for the accessing it .Public domain provide public to use the service of the domain.

Other given option are incorrect as shareware stage is for the sharing purpose of the data,private realm is the sector having private services, dustbin is for the waste and not required services.Thus, the correct option is option(d).

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