Choice "B" is correct. Trading securities are reported at fair value, with holding gains and losses included in earnings.
Choice "c" is incorrect. Lower of cost or market valuation is not permitted under IFRS or U.S. GAAP.
Choice "d" is incorrect. Lower of cost or market valuation is not permitted under IFRS or U.S. GAAP.
Choice "a" is incorrect. Trading securities are reported at fair value but there is no restriction on the recognition of holding gains.