What is the appropriate next step for the social worker when the mother of a 16-year-old client, currently in therapy for depression, reports that she believes her daughter took some pills?

A) Advise the mother to monitor the daughter's symptoms and call back if they worsen.
B) Contact emergency services and ask the mother to take her daughter to the nearest hospital.
C) Schedule an urgent therapy session to discuss the situation with the client and her mother.
D) Provide the mother with information on over-the-counter medications to determine potential risks.