the subject of first half sentence 'This is the largest clock in the world’ is 'clock',while the subject of the other half is 'the minute hand',it is a part of the clock.Therefore,in the sentence it ...Thanks for you reply.Why "where=on/in the clock" can't be used here? In attributive clause, "where" denotes a place, an activity and a range.I know the minute hand is part of the clock. To some degree, it is a best answer.