Explanation:

- Obstruction is something that blocks or impedes progress or movement. It creates difficulties in getting through.

- Option 1: Guesswork refers to making an estimate or conjecture without sufficient information. It doesn’t relate to blocking or hindering.

- Option 2: Construction involves building or creating something. It has an opposite effect to obstruction as it is constructive rather than hindering.

- Option 3: Destruction means the process of causing so much damage to something that it no longer exists or can be repaired. Although it can end an action, it’s not synonymous with obstruction.

- Option 4: Hindrance signifies something that provides resistance or delay to movement or progress. This is aligned with the meaning of obstruction.

Therefore, Option 4: Hindrance is indeed the most appropriate synonym for obstruction.

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