Answer: Step 10 - Luca connect six fluid connections.


The list of steps in the corresponding spacewalk mission:
Step 1 - Luca & Drew exit airlock with pump system.
Step 2 - Luca & Drew take pump system to external support platform 2.
Step 3 - Luca enter foot restraint on robotic arm.
Step 4 - Drew hands Luca the pump system.
Step 5 - Robotic arm takes Luca to AMS.
Step 6 - Drew move to ELC 2.
Step 7 - Luca & Drew install pump system.
Step 8 - Luca & Drew connect power and data cables.
Step 9 - Robotic arm takes Luca to aft side.
Step 10 - Luca connect six fluid connections.
Step 11 - Robotic arm takes Luca to underside of AMS.
Step 12 - Luca & Drew complete final 2 suages.
Step 13 - Robotic arm takes Luca to ESP 2.
Step 14 - Drew bring bags back to airlock.