The vulnerability that is most likely to affect an enterprise network after an upgrade is called the Weakest Link.
Because security relies heavily on trust, it is usually considered the weakest link in the security chain.
Because the third-party service provider is a utility provider, we may be quick to open up the network to them which leaves us vulnerable as we have absolutely no control over who is acting on their side and if they have other intentions.
The correct answer, therefore, is B.
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