What does the speaker mean a. The moving cost him much money. b. The moving made him very tired. c. The moving took him a lot of time. d. The moving made him lose many belongings.

某交流220kV架空送电线路架设双地线，铁塔采用酒杯搭，导线为LGJ-400/65（直径d=28mm），线间距离D12=D23=7.0m。请回答下列问题。

说明在高土壤电阻率地区，为提高线路雷击塔顶时的耐雷水平，应采用下列哪项有效措施？（）

A.减小地线对边相导线的保护角

B.降低杆塔接地电阻

C.增加导线绝缘子串的绝缘子片数

D.避雷线对杆塔绝缘