Which work unit are you from?
From China Digital Space
nǐ shì nǎge dānwèi de? 你是哪个单位的?
A question of condescension establishing power for the person who asks it. This phrase originated during the 11th National Games held in October of 2009. Before the diving competition had ended, a coach named Ma Ming claimed that all the gold medals for diving had already been determined by Zhou Jihong, Captain of the State Diving Team. He also correctly predicted the next four gold medal winners.
Reporters then asked Zhou whether or not the medals had been predetermined. Instead of directly answering the question, she shot back, “Which work unit are you from?” (Asking one's work unit is a loaded question, as it immediately creates a power dynamic between the person who asks and the person who answers.) The condescending tone of her question and her glib denial caught the interest of netizens who reposted the phrase on the Internet.