1121.1. For the purposes of Part I, where a trust in its fiscal return filed under this Part for a taxation year throughout which it was a mutual fund trust designates a particular amount, established for the year under section 1121.2, in respect of a particular unit of the trust owned by a taxpayer at any time in the year, the following rules apply:(a) the particular amount shall, subject to section 1121.4, be deductible in computing the income of the trust for the year;
(b) the particular amount shall be included in computing the income of the taxpayer for his taxation year in which the year of the trust ends, except that where the particular unit was owned by two or more taxpayers during the year, such part of the particular amount as the trust may determine shall, if the aggregate of all such parts is equal to that particular amount, be included in computing the income of each such taxpayer for his taxation year in which the year of the trust ends.