Final answer:
The transcontinental railroad took several years to build because a divided Congress continued fighting over funding for the railroad, resulting in work stoppages every few months.
Step-by-step explanation:
The statement that best explains why the transcontinental railroad took several years to build is that a divided Congress continued fighting over funding for the railroad, leading to work stoppages every few months. This prolonged the construction process and delayed progress. The disagreements and delays caused by the divided Congress hindered the smooth and timely completion of the railroad.
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