Which is simple and I can use it without any doubt anywhere. However, the below examples with "his" & "hers" are not that simple to me to use in my daily usage. I want to know how a native speaker would say this.
Or is it mandatory to use the object name whenever we use "his", "her",....
It's her pen
It's his pen
Question update to make it more clear:
I'm not asking about difference or which one is correct. I'm just asking, as a native speaker would you say "It's his" in your daily conversation. Because, for a non native speaker like me, "It's his" without using object name doesn't sound good whenever I say it.