Which of the following software license models allows a developer to modify the original code...

 Open source software is software that allows anyone to access, modify, and distribute its source code, which is the human-readable instructions that make up the software. Open source software encourages collaboration and innovation among developers and users. Examples of open source software include Linux, Firefox, and WordPress. Other types of software license models, such as proprietary and commercial software, restrict the access and modification of the source code. References : The Official CompTIA IT Fundamentals (ITF+) Study Guide (FC0-U61), page 122.