The lecturer has to make a choice (5)
I believe the answer is:
elect
'make a choice' is the definition.
(electing is a kind of making a choice)
'the lecturer has' is the wordplay.
'has' indicates the answer is hidden within the clue.
'ELECT' can be found hidden inside 'the lecturer'.
'to' acts as a link.
(Other definitions for elect that I've seen before include "Return" , "Vote into office" , "Choose by vote" , "Preferred" , "special people" .)