Identify the unfair aspect with respect to the sentence extracted from an online Terms of Service:
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the goods must be fully returned in the original packaging with the applicable proof of purchase , and you will be responsible for the cost of returning the goods to us . 

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. OPTIONS: ['Unilateral change' 'Contract by using' 'Content removal' 'Arbitration'
 'None' 'Choice of law' 'Limitation of liability' 'Jurisdiction'
 'Unilateral termination'].