One always estimates interest expense based on the carrying amount of the bond (in this case = 255,369,000e)
As a result, 255 369 000e * 0.06 = 15,322,140e for the whole year.
However, we only account for the time from Oct till End of 2016 (31st of Dec) --> Three months
15,322,140e *3/12 = 3,830,535e
Which should be Answer C.
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Your Success Formula Team - Florian