OK I will admit I did not list an Item D. But I did suggest that such a small organism likc coral would not be substantial enought to store rainwater thus I recognised the problem and dismissed it as a method that a tiny colony organism could apply unlike a much larger plants which can grow the structures to store rain water

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Note 1. All requests for planetary demolition must now be submitted in quadruplicate on form UX-565/B4 and be counter-signed by the assistant administrative officer for interstellar traffic calming - department QG-7. Subject to approval by the chief planning officer and the infrastructure development coordination sub-committee.