Rewrite the following sentence to move the adverbial clause to the beginning of the sentence.
The professor answered the student’s question quickly although he had been busy with his work.
Although he had been busy with his work, the professor answered the student’s question quickly.
Complete the following task based on the instruction and optional input provided.### Instruction:
Rewrite the following sentence to move the adverbial clause to the beginning of the sentence.

### Input:
The professor answered the student’s question quickly although he had been busy with his work.

### Output:
Although he had been busy with his work, the professor answered the student’s question quickly.