Arnold (an individual with a calendar year), Big Co. (a corporation with a June 30 fiscal year) and C Corp. (a corporation with a November 30 fiscal year) form ABC general partnership to operate a retail store selling sporting goods. ABC will be operated and managed by Arnold. Arnold contributes $450 cash for a 22.5% partnership interest; Bigco contributes $750 cash for a 37.5% partnership interest; and C Corp. contributes $800 of cash for a 40% partnership interest. What is the ABC Partnership's required tax year?