The Paris Bourse Was Traditionally a Call Market

The Paris Bourse was traditionally a call market. In a call market, an agent of the exchange accumulates, over a period of time, a batch of orders that are periodically executed by written or verbal auction throughout the trading day. Both market and limit orders are handled in this way. The major disadvantage of a call market is that

A) traders are not certain about the price at which their orders will transact because bid and ask quotations are not available prior to the call.
B) traders are not certain about how many shares will be able to sell or buy at the price they quote because order volume is not available prior to the call.
C) there is a lack of liquidity intercall.
D) none of the above