單項(xiàng)選擇題某規(guī)劃包含三個(gè)規(guī)劃項(xiàng)目,經(jīng)計(jì)算A規(guī)劃項(xiàng)目D10%為20km,B規(guī)劃項(xiàng)目D10%為30km,C規(guī)劃項(xiàng)目D10%為45km,則該規(guī)劃大氣環(huán)境影響評(píng)價(jià)范圍以規(guī)劃區(qū)邊界為起點(diǎn),外延()的區(qū)域。

A.20km
B.30km
C.45km
D.50km