What are the two methods of climbing towers while remaining attached at all times?

Choosing double legged lanyards and a vertical cable lifeline as the methods for climbing towers while remaining attached at all times is correct because both options provide crucial safety features that ensure fall protection.

Double legged lanyards, also known as "double lanyards," allow a climber to remain secured while transitioning between different anchor points. This is particularly important when navigating obstacles or changing positions on the tower, as it ensures that the worker is always connected to a secure point, minimizing the risk of falls.

The vertical cable lifeline functions as a fixed anchor point that allows the climber to ascend or descend the tower while remaining securely attached. It typically involves a cable system that a climber can clip onto using a safety harness. This setup not only allows for movement up and down but also ensures that the climber is continuously secured throughout the process.

Combining these two methods strengthens safety protocols for tower climbing, as they work together to prevent accidents effectively. Other options do not incorporate both of these critical aspects or may include components that do not provide the same level of continuous attachment.