Source set: A store table shows before-and-after data. Store A: visits rose from 1,000 to 1,200 and sales rose from $50,000 to $54,000. Store B: visits fell from 800 to 760 and sales rose from $40,000 to $41,800. An ad-spend chart shows both stores received the campaign. Which statement correctly evaluates the claim, 'Sales per visit improved in both stores after the campaign'?