Final answer:
The correct answer is option c) The murder remained unsolved.
Step-by-step explanation:
After the murder of Sergei Kirov in 1934, several significant events occurred in the long term.
First, the murder remained unsolved, although it led to the unraveling of a vast conspiracy that dominated the media for the next four years.
Second, the murder of Kirov and the growing feelings of paranoia in Stalin led to the beginning of the Great Purge, during which thousands of party members were targeted and senior officials were accused of counter-revolutionary crimes.
Finally, in the aftermath of World War II, Stalin's power was unshakable, and he enjoyed a period of genuine popularity as the powerful, protective leader of the Soviet people.