And if she had said 'no'? No choice?
Is the parallel here with 'irresistible grace'? Some can only say yes, some can only say no?
Those who can only say no, doomed to eternal hell. As determined before they/we are born.
Again, if one cannot choose otherwise, there is no choice in reality. And what we 'choose' becomes meaningless.
Do you think Moses had a choice? God told him that He had selected Moses and over-ruled Moses' objections.
Jeremiah was not given a choice. Despite his objections, God had selected him and that was how the plan unfolded.
The baby was going to be born from Mary's womb. That was God's plan.
Mary believed and submitted to the plan as Moses and Jeremiah also had done.
Faith comes because God creates it. Sometimes He has to work to convince. Others don't need a whole lot of convincing. That God brings faith doesn't mean we're robots. It means we in ourselves are set against His will (robotic if you will in purusing a sinful path) and it is He who moves to convince us otherwise.