As if a Hebrew girl would turn down the choice of being the mother of Christ. Luke records the interaction so we’d have an accurate record of what happened.
Luke wasn’t even alive or anywhere close. He couldn’t have recorded the interaction.
Clearly.
Now answer the questions.
Many Hebrew girls would have turned down that choice. Israel was famous for its idol worship and apostasy.
Plus, being "chosen" by God was rarely a path to an easy life. Many OT prophets suffered mightily during their ministries, as did all of Jesus' apostles.
Jonah and Moses actually tried to get out of being chosen for their missions.
So Mary is to be honored for her choice to accept.