Final answer:
The official C++ 2017 standards are defined by The C++ Standards Committee, which is an international group of experts that develop and maintain the standards.
Step-by-step explanation:
The correct answer is A) The C++ Standards Committee. The C++ Standards Committee is responsible for defining what goes into the official C++ 2017 standard.
The entity responsible for defining what goes into the official C++ 2017 standard is The C++ Standards Committee. This committee, also known as ISO/IEC JTC1/SC22/WG21, is an international body of experts who work together to develop and maintain the C++ programming language standards. The process of standardization involves proposal submissions, rigorous review, discussion, and refinement before a feature or modification is officially adopted.