Whose last name do you think a child should have?

I know that a lot of woman wants to have their last name to their kids because they never want a man's last name who they claim did nothing to make that child. So whose last name do you think a child should have? And what's your reason for that?
What about in cases where the father or mother left their kids life?
Mother
Father
Select gender and age to cast your vote:
Whose last name do you think a child should have?
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