Hi Laura,
this question does not ask you for any calculations. It just asks you to rearrange the table, incorporating now 2 index tests (B and T), which increases the possible combinations from a 2x2 table to a 2x4 table (given). The assumption that you might have missed is that T is perfect, i.e all T+ are D+ and all T- are D-.
Does that help?
Kerstin