Final answer:
The most important detail to include in a summary about space technology advancements is that there is new technology to make space tourism possible, as it represents a significant shift in the industry.
Step-by-step explanation:
When writing a summary of an article about new advancements in space technology, the key elements to include are significant updates that have the potential to change the industry. Among the possible statements, the most important to put in the summary would be 'A. There is new technology to make space tourism happen.' This point suggests a new development which has broader implications for the future of space travel and tourism, capturing a significant potential advancement in the field.
While other details such as SpaceX as a company, the rockets they build, and their specific projects like Starship are also important, they are more suited as supporting details rather than the central focus of an executive summary. The central focus should highlight the emergence of innovative technologies that could revolutionize our approach to space exploration and space-related activities.