Briefly explain how transcontinental railroads were completed and brought more settlers west.

The transcontinental railroads were completed as it has been considered to be the most ambitious engineering project that made it a priority for it to be accomplished and to be completed, after it has completed, it became more efficient in travelling in which those people living in the rural areas were able to travel to urban cities in search of employment and different things that would be beneficial for them.

Ithink b is the right answer