Southern Pacific Co

Southern Pacific Co. v. Arizona concerned whether Arizona could, for safety considerations, require trains traveling through the state be a shorter length than trains traveling through other states. The Supreme Court justified striking down the Arizona law because:

A) because the law did not concern a legitimate state interest to improve transportation safety
B) because Congress had passed legislation dealing with the length of trains
C) because the law conflicted with federal standards
D) because the law interfered with interstate commerce
E) none of the other choices