Actually the position of governer general of bengal is crated as per regulating act 1773.as per this warrenhastings who was the govorer of bengal at that time became the governor general (note that the designation only changed).then later the british govt passed charter act 1833,as per this the governor general of bengal during the time (william bentic)came to known as governor general of india.then as per queen's proclamation act 1858,the post name became viceroy..and governor general of india at that time(canning) redesignated as viceroy

As per psc rank files first governor general of india answer is Hastings. Even though it's Bentinck as per charter act. So mostly options won't include both names.

William bentic is the first governor general of india as per charter act 1833