Which of the following best describes how S-PMSI construction is initiated in Draft Rosen? 

The ingress PE sends an MDT Join TLV in the I-PMSI for a group address from the configured range. 

The egress PE sends an MDT Join TLV in the I-PMSI for a group address from the configured range. 

The ingress PE sends a PIM Join in the I-PMSI for a group address from the configured range. 

The egress PE sends a PIM Join in the I-PMSI for a group address from the configured range.