What is the relationship between grocery and Walmart in the context of the input sentence. Choose an answer from: product/material produced; manufacturer; distributed by; industry; position held; original broadcaster; owned by; founded by; distribution format; headquarters location; stock exchange; currency; parent organization; chief executive officer; director/manager; owner of; operator; member of; employer; chairperson; platform; subsidiary; legal form; publisher; developer; brand; business division; location of formation; creator.

Our active brands AND1, Avia, Gaiam and SPRI, which are sold at mass retailers, including Walmart and Target as well as grocery and drugstores nationwide, have seen strong retail sales during the pandemic.

Answer: operator