Which of the following represents the SAFECode secure design principle: "Defense in Depth"?

$1.$

Defense in Depth principle: a system should be designed to remain secure even if it encounters an error or crashes

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Defense in Depth principle: Design the system so that it can resist attack even if a single security vulnerability is discovered or a single security feature is bypassed.

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Defense in Depth principle: Plan for assigning multiple administrative roles, each with its own least privilege.

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Defense in Depth principle: Plan for the safe and reliable installation of security updates.