The Obligations of Sellers/lessors and Buyers/lessees Are Determined by Which

The obligations of sellers/lessors and buyers/lessees are determined by which of the following?

A) Terms the parties outline in agreements only
B) Custom only
C) Rules outlined by the Uniform Commercial Code only
D) Terms the parties outline in agreements, custom, and rules outlined by the Uniform Commercial Code
E) Terms the parties outline in agreements and custom, but not rules outlined by the Uniform Commercial Code