As to Ukrainian election, which of the following is true？A．Any of Russia's improper respon

As to Ukrainian election, which of the following is true？

A．Any of Russia's improper responses will cause political crisis in Ukraine.

B．Russia had rescheduled a lot of festivities before the actual date of the election.

C．Putin's congratulation has caused opposition between the two candidates.

D．The voting fraud reported by Kremlin caused a rally in protest.