​For the Following Question

Multiple Choice

​For the following question
Consider a simultaneous move game between a union and a company.If both the parties bargain hard,each would gain nothing.If only one party bargains hard the accommodating party gets a profit of $1 million while the bargaining party gets a $5 million,while if they both accommodate,they each get $3 million.
-​By threatening to lockout the workers,the firm has

A) ​Eliminated half of the strategies
B) Forced the union to choose the best response in the firm's best interest
C) Made it in the union's best interest to not strike
D) ​All of the above