A:x+2y-1='0'
B:2x+y-1='0'
C:2x+y-3='0'
D:x+2y-3=0
—Oh,God!Somebody________the cup.
—It wasn't me.I didn't do it.
读《悬岩边的树》,结合“孤单”“寂寞”“倾听”等词语,说说“悬岩边的树”有何象征意义?