user: Question: What is Doctor, when Format is CD, and when Title is The Relics of Time?
Columns: ['Title', 'Writer', 'Doctor', 'Format', 'Company', 'release date']
Types: ['text', 'text', 'text', 'text', 'text', 'text']
Sample row: ['Doctor Who and the Pescatons', 'Pemberton, Victor Victor Pemberton', '04 Fourth Doctor', 'LP Cassette', 'Decca', '1976-07-01 July 1976']
SQL:

assistant: SELECT "Doctor" FROM "Table" WHERE "Format" = 'CD' AND "Title" = 'The Relics of Time';