Pick out the odd pair.

From the given options - 

Watch - Clock: A watch and a clock are synonyms; they represent the same thing.

Milk - Tea: Milk is an ingredient used to prepare tea; their relationship is material-product.

Cloth - Apparel: Cloth is used to make apparel; this is a raw material-finished product relationship.

Ice - Water: Ice and water are different states (solid and liquid) of the same substance.

Watch - Clock is the odd pair because it represents synonyms, while the other pairs show relationships like material-product or transformation.