; or (B) if the Committee attempts to mitigate the risk under subsection (c) and determines that mitigation is inadequate to protect the national security of the United States, prohibiting the covered activity. (2) Seeking alternative enforcement The Committee shall consider other existing measures to address any risk described in paragraph (1) before taking any action under this subsection with respect to the covered activity. (3) Announcement by Committee Not later than 90 days after the date on which the Committee initiates a review under subsection (b), the Committee shall announce the decision of the Committee with respect to whether the Committee plans to take action pursuant to paragraph (1). (4) Findings by Committee The Committee may exercise the authority under paragraph (1) with respect to a covered activity only if the Committee finds that— (A) there is credible evidence that leads the Committee to believe that the covered activity poses a risk to the national security of the United States