Vertical lifelines must be:
- Anchored
- Independent
- Protected from damage

Horizontal lifelines must be:
- Secured to a scaffold
- Looped around suspension lines about the hoist and brake (on suspension scaffolds)
- Secured between stanchions

Choose the correct option:
a) Tied-off
b) Anchored
c) Tethered

Vertical lifelines must be: anchored, independent, protected from damage. Horizontal lifelines must be anchored. Therefore the correct Statement is b.

Explanation:

Climbers use a harness and tie into a rope team or to anchors like pitons or snow anchors for safety. The preferred arrangement is to use multiple anchors forming a symmetric "Y" with an angle (θ) less than 90° between them, as advised for reducing stress on the anchors.

Large angles can cause the stress on the anchors to be significantly higher than the actual load, potentially making two anchors less safe than one. The force at each anchor in terms of the load (L) and angle (θ) can be calculated using principles of physics.

For example, when θ is 0°, the system should theoretically experience no additional stress beyond the load itself. When θ reaches 180°, the configuration would be impractical as the force on each anchor would be extremely high, indicating a critical failure point.