A:各自具体的性状
B:全部的染色体
C:所有的基因
D:每对染色体中的一条染色体
—John didn't stop looking for a job _________ he got an offer from a German company.
—Lucky him. It's not easy for university graduates to get a good job now.
南京国民政府覆灭的标志是( )