Who among the following was called by Gandhiji as his Rajya Guru in May, 1915?

Mahatma Gandhi regarded Gopal Krishna Gokhale as his political guru (Rajya Guru). Gokhale, founder of the Servants of India Society, deeply influenced Gandhi's political ideology and moderate approach. Although Gokhale died in February 1915, Gandhi continued to acknowledge him publicly as his mentor in politics. Gandhi often said that Gokhale taught him the importance of working for the country with humility, patience and dedication.