; (2) have the authority to grant exceptions to, or waivers of, national security investigative requirements, including issuing implementing or clarifying guidance, as necessary; (3) have the authority to assign, in whole or in part, to the head of any Federal agency (solely or jointly) any of the duties of the Security Executive Agent described in subsection (b) or the authorities described in paragraphs (1) and (2), provided that the exercise of such assigned duties or authorities is subject to the oversight of the Security Executive Agent, including such terms and conditions (including approval by the Security Executive Agent) as the Security Executive Agent determines appropriate