Which of the following should be included in a good defense-in-depth strategy provided by object- oriented programming for software deployment?

Polyinstantiation is a database security concept that allows multiple rows with the same primary key at different classification levels to prevent inference attacks, and is not an object-oriented programming principle related to defense-in-depth.

Polymorphism allows objects of different types to be treated through a common interface and is primarily a design flexibility feature, not a security control that contributes to defense-in-depth.

Encapsulation bundles data and the methods that operate on that data within a class, hiding internal state from outside access and enforcing controlled interfaces. This data-hiding principle directly supports defense-in-depth by ensuring that internal implementation details are protected from unauthorized or unintended access. It acts as a security boundary within software, limiting the attack surface exposed by each object.

Inheritance allows a class to derive properties and behaviors from a parent class, which can actually introduce security risks by exposing inherited methods, making it a design reuse feature rather than a defense-in-depth mechanism.