Open source projects is the correct option.

Open source projects publish their source code publicly so developers around the world can inspect, test, and contribute fixes. This transparency and the use of public repositories enable coordinated security reviews, issue reporting, and patch submission from a global community which speeds detection and remediation of vulnerabilities.

Cloud Functions is incorrect because it describes a serverless deployment model or managed service and not a development model that implies community review. The security responsibilities and patching for cloud functions are usually handled by the cloud provider or the application owner rather than a worldwide contributor base.

Proprietary applications is incorrect because proprietary code is closed and controlled by a vendor. Security fixes typically come from that vendor and not from an open, global group of contributors who can freely review and patch the code.

Object oriented programs is incorrect because object orientation is a programming paradigm and not a distribution or collaboration model. Being object oriented does not make a project subject to community review and worldwide patch contributions.

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