In case of a partial redemption or call of securities or options, etc., priority will be accorded to customer accounts on a FIFO (first in-first out) basis. Alternatively, if there is no priority in time among respective customer accounts, then such redemptions or calls shall be allocated on a pro-rata basis; or, if more appropriate or preferable, then such allocation shall be effected as otherwise determined to be fair, reasonable, and practicable by management.