Final answer:
An effective tax planning strategy could be to shift deductions to B Corp and taxable income to D Corp to optimize the tax position and potentially reduce the overall tax liability.
Step-by-step explanation:
An effective tax planning strategy, using the entity variable, might be to shift deductions to B Corp and taxable income to D Corp. This strategy takes advantage of the lower tax rate of B Corp (10%) for deductions, which can reduce the overall tax liability for the related group. Shifting taxable income to D Corp (21%) can help minimize the tax burden compared to C Corp (36%). By strategically allocating deductions and taxable income among the entities, the related group can optimize their tax position and potentially reduce their overall tax liability.