Final answer:
Quill Corp. v. North Dakota is the court case that established the definition of nexus for state sales and use taxes, requiring a physical presence for states to mandate tax collection from out-of-state sellers. option (A)
Step-by-step explanation:
The court case that helps establish the definition of nexus for sales and use taxes is Quill Corp. v. North Dakota. In this landmark decision, the Supreme Court ruled that states could only require out-of-state sellers to collect sales tax if the seller has a physical presence, or nexus, within the state.
This ruling was pivotal in determining how state tax laws applied to companies conducting business across state lines, particularly with respect to mail-order and later, e-commerce businesses.