患者男，21岁，下颌呈相对后退位，下颌角大，口唇闭合呈现口唇肌肉紧张。覆Ⅲ度，覆盖7mm，磨牙远中咬合关系，上颁拥挤4mm，ANB为8°，SNA为81°，下颌无拥挤，下前牙略唇倾，Spee曲线曲度3mm

此患者在整平Spee曲线时，不宜采用下列哪项措施（）.

A.辅弓

B.节段弓

C.J钩

D.上颌斜面导板

E.以上都不是

Flow control is a function that prevents network congestion by ensuring that (1) do not overwhelm (2) with data. There are three commonly used methods for handling network congestion. (3) is used by network devices to temporarily store bursts of excess data in memory until they can be processed. (4) are used by receiving devices to help prevent their buffers from overflowing. (5) is a flow -control scheme in which the source device requires an acknowledgment from the destination after a certain number of packets have been transmitted.

2（）

A．transmitting devices

B．transmitted devices

C．receiving devices

D．received devices