Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: Testing the Completeness of the SDSS Colour Selection for Ultramassive,
  Slowly Spinning Black Holes
21
The categories of this paper are: adap-org
23
The categories of this paper are: solv-int
5
The categories of this paper are: gr-qc
35
The categories of this paper are: mtrl-th
19
The categories of this paper are: eess
29
The categories of this paper are: funct-an
3
The categories of this paper are: physics
25
The categories of this paper are: patt-sol
32
The categories of this paper are: atom-ph
15
The categories of this paper are: nucl-ex
9
The categories of this paper are: nlin
8
The categories of this paper are: hep-ex
10
The categories of this paper are: q-bio
22
The categories of this paper are: chao-dyn
36
The categories of this paper are: cmp-lg
4
The categories of this paper are: cond-mat