The illustrations (options) are not present in your question. But I got them online;
A an illustration of a truck carrying building materials
B an illustration of materials being moved onto building floors
C an illustration of the partially constructed building
D an illustration of a riveter bonding a pair of steel beams
Answer: B.) An illustration of materials being moved onto building floors.
Explanation:
Firstly, the title of the excerpt alone which is “The Building of Manhattan” gives enough evidence that a building process is going on.
Also, from the content of the excerpt shows the same thing.
Materials are being moved from a truck onto dump carts and raised by an elevator to the selected floor after which they are wheeled onto the track system which was installed in each floor.
Thereafter, they are moved to the spot where they are needed.
Therefore, the excerpt clearly illustrates that materials are being moved onto building floors.