freedom of choice; discretion
A set phrase meaning the right or ability to choose freely; often used in formal or legal contexts.
Consumers have freedom of choice.
Which university to attend is your choice.
自由選択 is a more compact compound noun with the same meaning, but 選択の自由 is a more common and natural phrasing.
Compound of 選択 (choice) + の (possessive particle) + 自由 (freedom). A straightforward phrase with no special historical derivation.