Don't worry about me. I'm old enough to think for ________.
A:himself
B:herself
C:yourself
D:myself
4+2=____
6+8=____
4+2+8=____
为了保护南极的生态环境,到南极考察的科学工作者不仅要把塑料等难以降解的垃圾带离南极,还要把粪便等生活垃圾带离南极,这是因为南极( )