问题详情

Whatwastheauthor"spurposewhenwritingthispassage？
A．Todiscussdifferentmethodsofpruning.
B．Tointroducesomecommonknowledgeofpruning.
C．Toexplainhowtreesdevelopdisease.
D．Togivepracticalinstructionforpruningatree.
请帮忙给出正确答案和分析，谢谢！