题干
---Who will address the students from our school this evening?
--- ______ to be the speaker.
--- ______ to be the speaker.
A：I am supposed
B：I will suppose
C：I have supposed
D：I was supposing
答案(点此获取答案解析）
A
殖脱毒的种苗，以保证该品种的品质和产量水平。这种通过分生组织离体培养获得种苗的过程不涉及细胞的（ ）