The correct answer is "ค. เทคโนโลยี" (technology). This is because the question is asking about what is an important factor in the continuous development of progress. Technology plays a crucial role in advancing and innovating various aspects of human life, including education, communication, transportation, and healthcare. It enables new discoveries, improves efficiency, and creates opportunities for further advancements. Therefore, technology is a key driving force behind the continuous progress and development of society.