If at any time the number of members of a grouping is reduced below two, and it carries on any trade, activity or business for more than one month while the number is so reduced, the following persons shall, if they know that the grouping is carrying on business with less than two members, be severally liable for the payment of the whole debts of the grouping contracted during that time, and may be severally sued thereof, namely:
(a) if the remaining member is a natural person, that person,
(b) if the remaining member is a partnership, every member of that partnership,
(c) if the remaining member is a body corporate, every person who was a director or other officer of the body corporate during the period mentioned in this Regulation.