- You may be looking for Lab 2A.
2A was one of the classes of Coal Hill School. Clara Oswald once took one of their art classes. During the Twelfth Doctor's imprisonment in the Prison, Clara asked the class to paint a placard with "SAVE THE DOCTOR". However, the students became confused and instead began to paint "SAVE DOT COTTON", famous EastEnders character. Clara decided to ask Class 2B instead. (PROSE: The Blood Cell)