Question Presented: Is the Board of Immigration Appeals’ interpretation of “a particular social group” as requiring an element of “social visibility” entitled to deference under Chevron U.S.A. Inc. v. Natural Resources Defense Council, Inc., 467 U.S. 837 (1984), as held by seven circuits, or is the requirement an arbitrary or impermissible interpretation of the statute, as the Third and Seventh Circuits hold?