Controls

Sir in fox industries question, the question stated that explain 3 application controls that should be adopted by Fox industries Co to ensure completeness and accuracy of input of purchase invoices. (3 marks)

Sir in this question if 1 application control I write that :

Check digits : It reduces risk of transposition errors, i.e errors occurring due to reversal of digits, This process uses algorithms to ensure accuracy.

So is this enough for scoring 1 mark OR do I need to elaborate and explain this point further in order to obtain 1 full mark?