Answer :
In the case of Bachiko congratulating her staff as one of her role as manager, then, she is using her reward power.
Reward power refers to a power possessed by a manager to give some type of reward to his/her surbodinates/employees as a means of influencing and motivating them.
- Now, Bachiko is congratulating her staff through the company-wide e-mail, the power possessed by him to do so is known as Reward power.
Therefore, the Option A is correct.
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