((a)) ** Imposition of penalty** If an organization fails to meet the disclosure requirement of section 6115 with respect to a quid pro quo contribution, such organization shall pay a penalty of $10 for each contribution in respect of which the organization fails to make the required disclosure, except that the total penalty imposed by this subsection with respect to a particular fundraising event or mailing shall not exceed $5,000.

((b)) ** Reasonable cause exception** No penalty shall be imposed under this section with respect to any failure if it is shown that such failure is due to reasonable cause.