(a) What was the quantum of funds that was set aside for scholarships and bursaries under the National Student Financial Aid Scheme but was ultimately not spent (i) in the (aa) 2011-12, (bb) 2012-13, (cc) 2013-14 and (dd) 2014-15 financial years and (ii) since 1 April 2016 and (b) what (i) are the reasons in each case and (ii) is being done to ensure that all scholarship and bursary money is awarded in each specified financial year?