A is true, B is true and C is false
hope it helps.
Building through the Sierra Nevada Mountains was very difficult and dangerous. Temperatures were freezing during the winter and in one year alone there were 44 storms.There was the great danger of an avalanche for the men working through 18 feet of snow and camping on the tunnels beneath it. Creating tunnels through the mountains required blasting with nitroglycerin. Advancing at one foot of mountain at a time, a total of 11 tunnels was created.
Based on my information, I believe that the higher authorities that would choose the prime ministers would actually be the "house of commons". Going back a few years, many of the "house of commons" actually did not have the responsibility in order to do this, but then, the government figured that it would be better if they were to handle on this responsibility.