When can Parliament make a provision regarding preventive detention according to this clause?
According to this clause, Parliament can make a provision regarding preventive detention when either of the following conditions is met:

1. The expiration of one year from the commencement of this Constitution (Seventh Amendment) Act, 1956.
2. Parliament passes a law under clause (7) of Article 22 before the expiration of one year from the commencement of this Constitution (Seventh Amendment) Act, 1956.