Which of the Following Would Be a Source of Vertical

Which of the following would be a source of vertical conflict?

A) Foot Locker decides to open a retail outlet next to a Nike store in a shopping mall.
B) A restaurant serves both Coke and Pepsi to its patrons.
C) Ansible Technologies Ltd.sells its portable planetariums to both colleges and high schools.
D) Microsoft provides HP laptops more prominent point-of-purchase locations in its retail stores than comparable laptops from Sony.
E) Long John Silver's decides to serve grilled burgers in addition to seafood.