A.LAC與LMC相交 B.代表最優(yōu)規(guī)模的SAC曲線過LAC曲線與LMC曲線的交點(diǎn) C.代表最優(yōu)規(guī)模的SMC曲線過LAC曲線與LMC曲線的交點(diǎn) D.代表最優(yōu)規(guī)模的SMC曲線通過代表最優(yōu)規(guī)模的SAC曲線的最低點(diǎn)