______ is a process of influencing the behaviour of people by making them strive voluntarily towards achievement of organisational goals.”

The correct option is Leadership.

In management and organizational behavior, Leadership is defined as the art or process of influencing people so that they will strive willingly and enthusiastically toward the achievement of group or organizational goals.
Unlike mere command or coercion, true leadership inspires and motivates individuals to voluntarily align their personal efforts with the objectives of the organization.

Here is why the other options do not fit the blank as precisely as leadership:
• Motivation is the internal state or drive that stimulates people to act, rather than the external process of influencing their behavior.
• Supervision refers to the direct overseeing and guiding of subordinates to ensure they perform tasks correctly.
• Communication is the exchange of information, ideas, or feelings between individuals, which serves as a tool for management but is not defined as the process of voluntarily aligning behavior toward goals.