Identify two situations in which the block header grows in a data block. (Choose two.)

The row directory portion of the block header stores one entry (a pointer offset) for each row stored in the block; as more rows are inserted and the row directory runs out of pre-allocated entries, the block header expands into the free space area of the block to accommodate the new pointers.

Row migration occurs when an updated row no longer fits in its original block and Oracle moves the row to a new block, leaving only a forwarding pointer in the original block - this does not cause the original block header to grow.

PCTFREE is a storage parameter that controls how much free space is reserved for future row updates; changing its value adjusts the threshold for when new inserts are allowed, but does not itself cause the block header to grow.

The Interested Transaction List (ITL) in the block header is initially sized by the INITRANS storage parameter; when concurrent transactions exceed the initial ITL slot count, Oracle dynamically allocates additional ITL entries by consuming free space from within the block, causing the block header to grow.