Answer:
A). An important key was held in a safe.
C). The banker was willing to kill the prisoner to avoid paying him 2 million dollars.
D). The banker lost all his money over the 15-year term.
Step-by-step explanation:
'The Bet' by Anton Chekhov relates the story of a bet between a banker and a young man which eventually explores the theme of frivolity of material wealth.
As per the question, the key events that were affected by the surprise in the story would be 'the detaining of an important key in the safe,' 'the banker's loss of all his money across the term of 15 year' and 'the banker's wish to kill the prisoner in order to prevent paying him the bet amount.' The banker realized that if he pays off the complete amount, he would end up in bankruptcy and therefore, he decides to murder the lawyer.