(a) Only a qualified person may be appointed a proxy to vote shares of a professional corporation.
(b) A voting trust with respect to shares of a professional corporation is not valid unless all of its trustees and beneficiaries are qualified persons. But if a beneficiary who is a qualified person dies or becomes disqualified, a voting trust valid under this subsection (b) continues to be valid for ten (10) months after the date of death or for five (5) months after the disqualification occurred.