The underlined phrase "to submit to" is closest in meaning to

A．The functions of the Department of Labor in America.
B．A serious problem threatening American economy.
C．The successful attempt of regulating sweatshops in America.
D．The seriousness of the problem of sweatshops in America.

A．It will become the country's 14th largest retail apparel manufacturer.
B．It hasn't acted according to the Workplace Cede of Conduct.
C．It has demanded its contractors to sign the Workplace Code of Conduct.
D．It has teamed up with the Department of Labor to launch a campaign.