Correct Answer: D
Compatibility is the ability of software or hardware to work with different types of software or hardware without errors or conflicts. Installing cross-platform software addresses the concern of compatibility because cross-platform software can run on multiple operating systems or platforms without requiring modifications or adaptations. Cross-platform software can reduce the cost and complexity of developing and maintaining software for different platforms. Subscription, licensing, and product key are not concerns that installing cross-platform software addresses. Subscription is the agreement or contract that allows users to access software or services for a certain period of time or frequency. Licensing is the permission or authorization that grants users the right to use software or services under certain terms and conditions. Product key is the code or identifier that verifies the authenticity or validity of software or services. References: CompTIA IT Fundamentals+ Study Guide: Exam FC0-U61, Second Edition, Chapter 7: Software Installation and Functions, page 265.