[Employee Picketing] Amir Owns a Unionized Business Called "Amir's Furniture

[Employee Picketing] Amir owns a unionized business called "Amir's Furniture" that manufactures furniture.Employees are unhappy because they believe that during negotiations for a collective bargaining agreement,Amir is improperly refusing to give them a raise.The employees stop working for Amir's business and begin picketing.At first the employees carry signs with slogans such as "Labor Dispute - Amir Won't Pay a Fair Wage," meant to inform the public that a labor dispute has resulted because Amir is cheap.When that,however,fails to change Amir's mind,the employees begin staging pickets to prevent deliveries to Amir and to prevent access to employees who want to work.They carry signs saying "No Access to Amir - Shut Him Down."
-Which of the following is the appropriate term for the work stoppage engaged in by the employees?

A) A strike
B) A lockout
C) A walk out
D) A slow down
E) A sit down