In the following statements, select those that are correct. a. In B-tree insertion, we use linear search to identify an appropriate key to branch. This implementation incurs O(log n) CPU time, independent of t. b. Inserting the key {1,2,,n} with n>1 into an empty B-tree with minimum degree 2, the final B-tree has (n) nodes. c. A redundant DISK-READ is a DISK-READ for a page that is already in memory. A redundant DISK-WRITE writes to disk a page of information that is identical to what is already stored there. Inserting a key into a full child incurs at least two redundant DISK-READ and two redundant DISK-WRITE. d. Given the following B-tree with degree t=3 : After deleting V, the new tree is