Hindley put out his tongue, and cuffed him over the ears.

‘You’d better do it at once,’ he persisted, escaping to the porch (they were in the stable): ‘You will have to; and if I speak of these blows, you’ll get them again with interest.

'Off dog!' cried Hindley, threatening him with an iron weight used for weighing potatoes and hay.
In this excerpt from the passage, what does the phrase an iron weight mean?
A) This is a metaphor for a dog leash.
B) This is a literal weight made of iron.
C) This is both a literal and a figurative expression.
D) This is a idiomatic expression, like a "weight off my shoulders."