The correct answer is C. towards.
The preposition “towards” is used to indicate the direction or position of something in relation to something else. In this case, the treatment is being given “towards” the subordinates. This means that the treatment is being directed at the subordinates, and it is having an effect on them.
The other options are not as appropriate in this context. The preposition “of” is used to indicate possession or ownership. The preposition “for” is used to indicate a purpose or destination. The preposition “to” is used to indicate a destination or recipient. The preposition “about” is used to indicate a topic or subject.
In conclusion, the correct answer is C. towards.