In the context of the input sentence, determine the relationship between 'Admiral Group' and 'Cardiff'.
Options: stock exchange, platform, headquarters location, product/material produced

Admiral Group (LSE: ADM.L - news ) topped the risers after it announced expansion plans to take on 280 extra staff: 130 in its Newport (NasdaqGS: NEWP - news ) office, 50 in Cardiff and 100 in Swansea.
headquarters location