Why should soldered joints not be used in lightning protection ground connections?
A soldered joint will likely be destroyed by the heat of a lightning strike✓Correct answer
Solder flux will prevent a low conductivity connection
Solder has too high a dielectric constant to provide adequate lightning protection
All these choices are correct
Explanation
A lightning strike delivers tens of kiloamps, and the resistive heating in the joint is far more than enough to melt the solder, which liquefies at under 200 degrees Celsius. The connection would open at the moment it is most needed, so lightning ground connections use clamped, crimped or exothermically welded joints instead.