Which two hints are taken initially? (4)
I believe the answer is:
that
'which' is the definition.
('that' and 'which' are often synonymous)
'two hints are taken initially?' is the wordplay.
'initially?' indicates taking the first letters (I've seen 'initially' mean this).
The first letters of 'two hints are taken' is 'THAT'.
(Other definitions for that that I've seen before include "Yon" , "The (one) there" , "See 5" , "Take ..., English pop band" , "Just like --; -- is to say" .)