what does blue teaming mean?

In the context of penetration testing, what does blue teaming mean?

A.
A penetration test performed with the knowledge and consent of the organization’s IT staff

B.
It is the most expensive and most widely used

C.
It may be conducted with or without warning

D.
A penetration test performed without the knowledge of the organization’s IT staff but with
permission from upper management

Explanation:

Reference:
https://www.sypriselectronics.com/information-security/cyber-securitysolutions/computernetwork-defense/