According to paragraph 2, which of the following is true of the map published by William S

According to paragraph 2, which of the following is true of the map published by William Smith？

A．It indicates the locations of England"s major canals.

B．It became most valuable when the steam locomotive made rail travel possible.

C．The data for the map were collected during Smith"s work on canals.

D．It is no longer regarded as a geological masterpiece.

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