Z plc provides a single service to its customers. An analysis of its budget for the year ending 31 December shows that in period 4, when the budgeted activity was 5220 service units with a sales value of £42 each, the margin of safety was 19.575 per cent. The budgeted contribution to sales ratio of the service is 40 per cent. Budgeted fixed costs in period 4 were nearest to

(a) £1700

(b) £71 000

(c) £88 000

(d) £176 000