单选题 The settlement price for a futures contract is:

A、 an average of the trade prices during the " closing period"
B、 the price of the last trade of a futures contract at the end of the trading day.
C、 the price at which all trades over a certain period are executed.

【正确答案】 A

【答案解析】The margin adjustments are made based on the settlement price, which is calculated as the average trade price over a specific closing period at the end of the trading day. The length of the closing period is set by the exchange.