Choice "C" is correct. While most of the information in the item is correct, it is when over 60% of the adjusted gross income of a closely-held (more than 50% owned by 5 or fewer individuals either directly or indirectly at any time during the last half of the tax year) corporation consists of "NIRD" that it is defined as a personal holding company, not over 50% (as in the selection).
Choice "a" is incorrect, as the additional tax is self-assessed by the taxpayer by filing a separate schedule 1120PH along with the Form 1120.
Choice "d" is incorrect, as the accumulated earnings tax indeed does not apply to personal holding companies (which are not allowed to accumulate any earnings without penalty!).
Choice "b" is incorrect. Provided the net earnings are distributed, there is no penalty.