Jason knows that his Apple system uses a separate portion of its SoC (system on chip) to store keys and biometric information. What is this specialized component called?

Apple devices use a specialized, separate coprocessor that uses encrypted memory and storage as well as dedicated cryptographic functions called a secure enclave. This is distinct from a TPM or HSM, and a screened subnet is a networking concept for a space that will be exposed to the less secure zones while needing to remain secure.