Rent-A-Center ‘s shares were rising midday Tuesday after activist investor Engaged Capital LLC’s Glenn Welling escalated his campaign at the furniture and electronics rent-to-own company with a letter suggesting that the “most logical” outcome from a strategic review process is a sale of the enterprise. The letter, addressed to the company’s board, also said that Welling was prepared to nominate a slate of dissident director candidates if the company didn’t act “objectively and expediently” for all shareholders.