_________ great day! Let's go out to have a picnic.
A:What a
B:What
C:How
D:How a
We want to rent a bus which can __________ 40 people for our trip to Beijing.
在离体的植物器官、组织或细胞脱分化形成愈伤组织的过程中,下列哪一项条件是不需要的