Short answer: (c) is correct.
Do I take it that you are responsible for both the account and the student’s CTB claim? Sounds like it.
If so, I believe you should do the following:
– the property loses its exemption and the student becomes liable to pay the tax
– because he is “invisible”, there is only one “visible” resident so the full tax is reduced by 25% single person discount
– full time students are not excluded from 2AR, so he can claim that
– if his mother had been on IS/JSA-ib/PC he would have got 2AR to cover 100% of the remaining liability after discount: but you say she has some other income so that doesn’t apply
– therefore, 15% 2AR is awarded in accordance with CTB Sched 2. Here, it is important to read the fine print. Paragraph 1(2) as amended from April now says that the percentage reduction is applied to the claimant’s tax after any “reductions” under the LGFA, and in addition where a student has a non-dep on IS/JSA-ib/PC after any discount. This means that in all cases [b:f546c5c3e6]except [/b:f546c5c3e6] the new rule giving students 100% 2AR, the percentage 2AR award is based on the full original tax (before the 25% discount was taken off) but after allowing for any disability reduction.
In your case, therefore, 2AR is 15% of the full amount, not 15% of 75%.
So in short, the combination of discount and 2AR reduces the full tax by 40%.