What is the difference between boost rules and promoting items? (2)

What is the difference between boost rules and promoting items? (2)
A . Boost rules are defined globally while promoted items are category aware
B . Boosting an item priorizes it more than promoting an item does
C . Boost rules are attribute-focused while promoted items are product-focused
D . Promoting an item prioritizes it more than the boost rules do

Answer: C,D