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