For purposes of subparagraph (A), in the case of any benefits provided through a salary reduction agreement, a plan may disregard any employees whose compensation is less than $25,000. For purposes of this subparagraph, the term “compensation” has the meaning given such term by section
414
(q)(4), except that, under rules prescribed by the Secretary, an employer may elect to determine compensation on any other basis which does not discriminate in favor of highly compensated employees.