The second sentence is grammatically correct. `Majority of’ is invariably followed by a plural noun. For example, we say, `majority of students’, `majority of young mothers’ and `majority of cases’. Since the noun in all the examples is plural, the verb that follows must also be plural.
*The majority of students are unwilling to take part in the strike.
When `the majority’ is not followed by `of’, then the verb that follows can be either singular or plural. For example,
*The majority is of the opinion that we must go on strike. *The majority feel threatened by the possible changes.