To create a flex-algo instance in a network, which of the following configuration steps is...

To create a flex-algo instance in a network, it's mandatory to configure at least one router in the network to create and advertise the flex-algo definition, This is the first step in creating a flex-algo instance, and it's done by defining the flex-algo instance and its properties on one or more routers in the network.

The other steps are important to fine-tune the flex-algo instance, but not mandatory to create it.

Configuring the proper values for the shared-risk link groups (SRLGs) that will define the flex-algo topology.

Specifying whether the LSP paths will be computed locally or by an external path computation element (PCE).

Configuring LSPs between every pair of PE routers.