Concept:Liquidity ratio is the minimum share of total deposits that a commercial bank must hold as liquid assets like cash and convertible paper.Explanation:Commercial banks accept deposits from the public.They must keep a fixed proportion of these total deposits in liquid form.This liquid form includes cash and convertible paper, which can be quickly used to meet withdrawals.This required proportion is known as the liquidity ratio.It is different from special deposits, interest rates, or bank rates.Answer:B. liquidity ratio