The death of a college student with cancer has drawn attention to Baidu Inc.’s advertising practices. The Wall Street Journal reports that Baidu faced harsh criticism from online users and state media following the death of Wei Zexi, a college student, after he and his family found an alternative cancer treatment through a sponsored Baidu link. Chinese authorities have launched an investigation of the search giant, and the State Administration for Industry and Commerce said last week it was cracking down on questionable Internet-advertising practices. Baidu’s stock has fallen more than 9% since reports of the investigation surfaced last week.