One electronic product manufactured by the branch in country X is very popular in Country Z. The production cost is $120 per unit. In past, the product was sold to Retailer Company (an unaffiliated company) in Country Z at the price of $180 per unit. Assume BPC would set up a subsidiary in Country Z to take charge of the sales of the product. 

Consider this case and determine the best transfer pricing method and appropriate transfer price. Please select only one transfer pricing method as the best from these 5 options. 

1. Comparable uncontrolled price method 

2. Resale price method 

3. Cost-plus method 

4. Comparable profits method 

5. Profit split method