Identify the unfair aspect with respect to the sentence extracted from an online Terms of Service:
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you must be 18 years of age , or the age of majority in your province , territory or country , to sign up as a registered user of the products . 

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