Fill in the blank: Mark Wiedman, global head of BlackRock Inc. BLK 2.51 % ’s iShares unit, defended how an iShares ETF performed during recent market turmoil, saying it only “had ____ where it didn’t function properly.”
Refer to the input text as context and select the correct relationship between 'iShares' and 'BlackRock' from the available options.
Options: headquarters location, legal form, original broadcaster, operator