Answer:A. monstrous
Step-by-step explanation:
The word "monstrous" could be a suitable replacement for the phrase "colossal gigantic" in this context because both words convey the idea of something very large and impressive. The word "monstrous" often implies a sense of enormity and size, which aligns with the meaning of "colossal gigantic" in describing the machinery of the State as being of great size and magnitude