The revenue to be added as an adjustment is?

At the end of a financial period, the trading
profit and loss account of a sole trader
shows a profit of #180,000. it is however
discovered that revenue of #15,000 is
recorded as expenses while expenses of
#4,000 is recorded as revenue.

A. #34,000
B. #30,000
C. #15,000
D. #4,000

Correct Answer:

Option B – #30,000