Concept:This sentence uses the second conditional, which expresses an unreal or hypothetical situation in the present or future.
Explanation:The clause "Had I the wings of a bird" is an inverted form of "If I had the wings of a bird."
This inverted clause is in the past indefinite tense (subjunctive mood).
In the second conditional, when the if‑clause uses the past indefinite tense, the main clause must follow the pattern:
subject + would/might/could + base form of the verb (v1).
Thus, the correct completion is "I would fly away."
Option A: "I would fly away" correctly uses "would + fly."
Option B: "I should fly away" uses "should," which is not standard for a hypothetical wish.
Option C: "I will have flown away" uses a future perfect tense, which does not match the second conditional.
Option D: "I could have flown away" uses a perfect modal, which is for past unreal situations, not present/future hypothetical ones.
Therefore, only Option A follows the second conditional rule correctly.
Answer:A. I would fly away.