Concept:
Geographical arrangement of cities requires knowledge of their relative longitudinal positions. For the United States, this involves identifying which cities are on the East Coast, the Midwest, and the West Coast.
Step 1: Identifying the location of each industrial centre.
• A. Boston: Located on the Atlantic coast in the Northeast (Massachusetts). It is the easternmost city in this list.
• D. Pittsburgh: Located in western Pennsylvania. It is west of the Atlantic coast but east of the Midwestern plains.
• B. Chicago: Located in the Midwest (Illinois) on the shores of Lake Michigan. It is significantly further west than Pittsburgh.
• C. Seattle: Located in the Pacific Northwest (Washington). It is the westernmost city in the list.
Step 2: Arranging in East to West order.
The progression from the Atlantic to the Pacific is: Boston (A) $\rightarrow$ Pittsburgh (D) $\rightarrow$ Chicago (B) $\rightarrow$ Seattle (C).
Step 3: Conclusion.
The correct sequence is A, D, B, C.