What term describes something that obstructs progress or the creation of something?

The term that most accurately describes something that obstructs progress or the creation of something is "Impediment." An impediment is generally understood as a hindrance or obstacle that directly prevents advancement or completion of a task. In many contexts, it refers to a specific limitation or difficulty that must be overcome in order for progress to occur, making it the most suitable choice among the options provided.

While "Obstruction" is also a strong contender and relates to something that blocks or hinders progress, it tends to imply a more physical barrier. "Barrier" often suggests a more permanent or fixed obstruction, while "Interference" refers to a disruption in a process but does not specifically denote an obstacle in the same way an impediment does. Hence, "Impediment" is the term that most directly captures the essence of obstructing progress or creation.