Britain justified its taxation of the American colonies using a variety of arguments, but the most relevant points from your list would include:
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Because the colonies needed to help pay back the debt Britain accrued during the French and Indian War. After the French and Indian War (1754-1763), Britain incurred significant debt. The British government believed that the colonies, as beneficiaries of British military protection during the war, should contribute to paying off this debt through taxes.
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It was in the British constitution. Although not a direct justification, British officials often referred to existing laws and practices that supported taxation. They believed that, as subjects of the British Crown, the colonists were inherently obligated to pay taxes.
The other points mentioned—such as demands from the Church of England or agreements made by colonists before their departure—do not have strong historical foundations regarding the justification for tax policies and were not significant arguments used by Britain at the time.
Overall, the primary justification centered around the financial burdens following the war and the concept of colonial obligation to the British Empire.