Choose the correct answer. We always have a ... of cereal in the kitchen.

The correct answer is 'box' because cereal is typically sold in boxes. While 'kilo' refers to weight and 'loaf' to bread, and 'boxes' is plural, 'a box' is the most appropriate singular unit for cereal packaging in this context. Therefore, the sentence should be: 'We always have a box of cereal in the kitchen.'