Title 18 of the United States Code governs child pornography. See Chapter 110, Sexual Exploitation and Other Abuse of Children. 18 U.S.C. § 2256 defines "Child pornography" as:
"any visual depiction, including any photograph, film, video, picture, or computer or computer-generated image or picture, whether made or produced by electronic, mechanical, or other means, of sexually explicit conduct, where -
(A) the production of such visual depiction involves the use of a minor engaging in sexually explicit conduct;
(B) such visual depiction is, or appears to be, of a minor engaging in sexually explicit conduct;
(C) such visual depiction has been created, adapted, or modified to appear that an identifiable minor is engaging in sexually explicit conduct; or
(D) such visual depiction is advertised, promoted, presented, described, or distributed in such a manner that conveys the impression that the material is or contains a visual depiction of a minor engaging in sexually explicit conduct . . ."