Sofia wants to see serum Z, of which serum K is based on, for herself.
Travel to the West Tek research center and retrieve serum Z from the research wing. Return it to Sofia to complete the quest. Beware of the high number of powerful super mutants and mutant hounds that guard the facility due to it being their birthplace, and the doors to the research wing being mag-locked unless having the password to use the terminals to override the mag-locks temporarily to gain entrance.
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