When computing the row size for a table row, what overhead should be accounted for?

A: 48 bytes for ROWID, CREATEXID and DELETEXID only B: 32 bytes for ROWID. CREATEXID, DELETEXID and the null vector C: 32 bytes for ROWID. CREATEXID and DELETEXID and a variable number of bytes for the null vector if there are nullable columns D: 24 bytes for ROWID. CREATEXID and DELETEXID plus null vector if there are nullable columns and record header depending on string columns