The correct answer is option 4, San Francisco. The headquarters of the Ghadar Party was located in San Francisco. The Ghadar Party was a political organization formed by Punjabi Indians in 1913 with the goal of overthrowing British colonial rule in India. The party aimed to achieve Indian independence through revolutionary means. San Francisco, specifically the city`s South Asian community, was chosen as the headquarters due to its large population of Punjabi immigrants at the time. The party used its headquarters to coordinate and plan revolutionary activities, including the publication of a newspaper called "Ghadar" that spread nationalist ideology and encouraged Indians to rise up against British rule.