Answer:
C. Purchase of a trademark.
Step-by-step explanation:
Counter balancing error is when an error made cancel out another error. For instance, if an expense was charged to year A instead of year B. It means that there would be an over statement of expense and understatement of profit in year A whereas year B would have an understated expense and overstated profit. The retained earning say for year C would be correct due to the fact that the two previous errors cancelled out each other. Although the two errors were correct over two year period, yet the annual net figures for both years have always been mistated.
With regards to the above, all the options except purchase of trade mark are counter balancing errors which automatically offset each other in the next accounting periods.