Final answer:
Transformational leadership is the style where a leader empowers the team, encourages responsibility, seeks advice, and trusts the team, and research supports its effectiveness over transactional leadership styles.
Step-by-step explanation:
The leadership style described where a team member is encouraged to take on many responsibilities, seeks advice from the team in decision-making, is not overly controlling, allows the team to set its own goals, and trusts the team, is known as transformational leadership. This style is characterized by leaders who are charismatic role models, inspirational, intellectually stimulating, and who show individual consideration towards team members. They aim not only to lead but also to inspire and empower their followers to achieve higher levels of performance and personal development.
Research by Eagly, Johannesen-Schmidt, & van Engen (2003) has indicated that transformational leadership approaches are more effective compared to transactional leadership styles, which focus on supervision, organizational goals, rewards, and punishments to achieve compliance from team members.