Have sufficient training on safe tower climbing techniques
Use appropriate tie-off to the tower at all times
Always wear an approved climbing harness
All these choices are correct✓الإجابة الصحيحة
الشرح
Tower climbing is fall-hazard work, so all three apply: proper training, an approved climbing harness, and being tied off to the structure at all times, including while moving. Each protects against a different part of the risk, so the all-of-these answer is correct.