Section 51.503 - General pricing standard(a) An incumbent LEC shall offer elements to requesting telecommunications carriers at rates, terms, and conditions that are just, reasonable, and nondiscriminatory.(b) An incumbent LEC's rates for each element it offers shall comply with the rate structure rules set forth in §§ 51.507 and 51.509 , and shall be established, at the election of the state commission-(1) Pursuant to the forward-looking economic cost-based pricing methodology set forth in §§ 51.505 and 51.511 ; or(2) Consistent with the proxy ceilings and ranges set forth in § 51.513 .(c) The rates that an incumbent LEC assesses for elements shall not vary on the basis of the class of customers served by the requesting carrier, or on the type of services that the requesting carrier purchasing such elements uses them to provide.