In the context of the input sentence, determine the relationship between 'grocery' and 'Walmart'.
Options: operator, subsidiary, member of, platform

Reddit Email Print Reprint NEW YORK ( TheStreet ) --  Walmart ( WMT - Get Report ) stock is increasing by 0.42% to $63.93 in mid-morning trading on Tuesday, after the company announced it will expand a service that allows customers to pick up their online grocery orders from store parking lots.
operator