With reference to reservations in promotions in government jobs, consider the following statements:
1. The Nagaraj case (2006) relates to the issue of reservations in promotions.
2. The Supreme Court has upheld the application of creamy layer principle to members of the Scheduled Caste/Scheduled Tribe communities in promotions.
3. State is not bound to make reservations for SC/ST in the matter of promotions.
4. A state has to collect quantifiable data showing backwardness of the class to provide reservation in promotions to the SC/ST communities.
How many statements given above are correct?