we konw nothing about the man over there except ___he is American.A what B that C if D / 为什么选B 不选D 后面已经有he做主语了,可以不用that啊

we konw nothing about the man over there except ___he is American.
A what B that C if D / 为什么选B 不选D 后面已经有he做主语了,可以不用that啊

except后接名词或代词,except that 后接从句.