Instruction: Rank the products A, B, C, ... based on their relevance to the provided query, and produce a ranked list with the most relevant product positioned at the top of the list.

Input:
Query: smart keychain
Product list:
A: KeySmart CleanKey (1-pack)
B: KeySmart Pro - Compact Key Holder w LED Light & Tile Smart Technology, Track your Lost Keys & Phone w Bluetooth (up to 10 Keys, White)
Answer: B,A