The development of the hydrogen station network would be greatly affected by the process of ____________ of storage technology.

A．The job is not rewarding but challenging.
B．The job is both challenging and rewarding.
C．The job has both its strength and weakness.
D．The job is hard work and the pay is not satisfactory.

A．What is so-called Thanksgiving Day.
B．How to celebrate Thanksgiving Day.
C．The exact time of Thanksgiving Day.
D．The history of Thanksgiving Day.