JP Corporation Had Net Income of $1,000,000 for 2011

JP Corporation had net income of $1,000,000 for 2011. After issuing its financial statements, it realized that it had failed to include inventory from one of its small warehouses for several years. Specifically, it forgot to include $20,000 on December 31, 2010, and $30,000 on December 31, 2011. Which of the following is true regarding JPs 2011 net income?

A) Net income was understated by $10,000.
B) Net income was overstated by $10,000.
C) Net income was understated by $30,000.
D) Net income was overstated by $30,000.