What are some sources of stray current, according to common knowledge?

Stray current refers to unintended electrical currents that can flow through the ground or conductive materials due to various industrial activities or natural phenomena. Option B identifies some of the primary sources of stray current, which include telluric currents, welding operations, and electric transit systems.

Telluric currents are natural, low-frequency electric currents that flow through the Earth, arising from a variety of sources, including solar activity and electromagnetic waves from lightning strikes. These currents can impact cathodic protection systems and lead to corrosion if not managed appropriately.

Welding operations can also be a source of stray current. When welding equipment is used, it generates electrical currents that can inadvertently spread through the ground, especially in cases where the welding setup is not properly grounded. This can create localized areas of corrosion on nearby structures exposed to the stray current.

Electric transit systems, such as electric railways, use direct current (DC) to power trains. When these systems operate, leakage currants can occur, where some of the current flows into the ground instead of returning through the intended circuit. This stray current can cause corrosion of nearby metal structures, reinforcing the importance of understanding its sources in cathodic protection.

In contrast, the other options do not accurately reflect recognized sources of stray current