The following is an incomplete closed-loop system used at Biocan, a large company. It shows how the company reduces waste from their drink products.

Graphic shows fives circles placed in a closed loop. Consumer purchases and drinks from the aluminum can. leads to Empty cans are discarded into a recycling container. leads to Fuel-efficient vans collect and transport containers. leads to a blank circle leads to Materials are manufactured into new cans and sold.
Based on how closed-loop systems operate, which of the following is the most likely missing piece in their system?

Cans are shredded for reuse at wind-powered facilities.
Cans are smashed and sold to other recycling companies.
Foreign companies purchase discarded cans by the pound.
The company redirects the collected containers to the city.