A. Its aim was to remove from dance, any external associations, so that the dancers could concentrate on pure movement and pure pattern.

B. Abstract dance was the name of a specific style of ballet, devised in the 1920s and developed at the bahaus.

C. Ballroom dancing, for example, is concerned with the pleasure the movement and pattern-making give to the dancers, and not with some external 'programme.'

D. In the wider sense, a great deal of dance is ‘abstract’.

Here, Sentence B clearly defines what abstract dance is, when it was devised, and where it was developed. This appears to serve as a foundation for the rest of the paragraph, such that we move from a specific topic to a broader subject. Sentence A naturally follows because it expands on what abstract dance aimed to achieve. It explains that abstract dance sought to remove external associations so that dancers could focus purely on movement and patterns. This is a direct elaboration of what was introduced in B. In an exam setting, this understanding should allow us to eliminate Options C and D. Furthermore, since Sentence C does not directly flow from A, we can discard the arrangement DBAC in Option A.

Regardless of the above arrangements, we observe that sentences D and C can be linked. Sentence D presents a new perspective: it generalizes the idea of abstraction in dance. It says that abstract dance isn’t just limited to the points in B and A - many forms of dance can be considered 'abstract'. This smoothly connects the specific point in B-A to a wider context. To make this earlier point clearer, we can now add an example to illustrate how abstraction applies beyond ballet. This is where Sentence C comes in: it provides a real-world example of a dance form (ballroom dancing) that aligns with the idea of abstraction.

Hence, Option B presents the best arrangement: BADC.