Computer Security Incident Response Team (CSIRT) provide?

Which vital role does the U.S. Computer Security Incident Response Team (CSIRT) provide?

A.
Incident response services to any user,company,government agency,or organization in
partnership with the Department of Homeland Security

B.
Maintenance of the nation’s Internet infrastructure,builds out new Internet infrastructure,and
decommissions old Internet infrastructure

C.
Registration of critical penetration testing for the Department of Homeland Security and public
and private sectors

D.
Measurement of key vulnerability assessments on behalf of the Department of Defense (DOD)
and State Department,as well as private sectors