Utilize the input text as a context reference, choose the right relationship between 'grocery' and 'Walmart' from the options.
Options: location of formation, subsidiary, operator, platform

Walmart will offer the online grocery pickup at select stores in Atlanta; Charlotte and Fayetteville, N.C.; Salt Lake City; Ogden, Utah; Nashville, Tenn.; Tucson, Ariz.; and Colorado Springs, Colo.
operator