问题详情

In the last paragraph, what is meant by "cognitive cost"？
A．the amount of time that the writer spends writing a report
B．the reader"s unwillingness to make an effort to understand a report
C．the amount of time that the reader spends reading any report
D．the writer"s difficulty in presenting reports in an easily-understood style请帮忙给出正确答案和分析，谢谢！