I would like to play with you, _______ I have to do my homework first.
A:or
B:so
C:and
D:but
某同学在用显微镜观察人口腔上皮细胞临时装片时,希望能在视野中看到更多的细胞,你认为他应选择的目镜和物镜的组合是( )