NO.PZ2023010401000161
问题如下：
In practice, both a fixed parity regime and a target zone regime allow the exchange rate to float within a band around the parity level. The most likely rationale for the band is that the band allows the monetary authority to:
选项：
A.be less active in the currency market.
B.earn a spread on its currency transactions.
C.exercise more discretion in monetary policy.
解释：
Fixed exchange rates impose severe limitations on the exercise of independent monetary policy. With a rigidly fixed exchange rate, domestic interest rates, monetary aggregates (e.g., money supply), and credit conditions are dictated by the requirement to buy/sell the currency at the rigid parity. Even a narrow band around the parity level allows the monetary authority to exercise some discretionary control over these conditions. In general, the wider the band, the more independent control the monetary authority can exercise.
中文解析：
固定汇率严重限制了独立货币政策的实施。在严格固定的汇率下，国内利率、货币总量(如货币供应量)和信贷条件都是由按严格平价买卖货币的要求决定的。即使是在平价水平附近的狭窄区间内，货币当局也可以对这些条件行使一些自由裁量的控制。一般来说，浮动区间越宽，货币当局行使的独立控制能力就越强。
麻烦助教老师解释下这道题
