If Total Liabilities Decreased By $¥ 30,000$ And Equity Decreased By $¥10,000$

If total liabilities decreased by $¥ 30,000$ and equity decreased by $¥10,000$ during a period of time, then total assets must change by what amount and direction during that same period?

A) $¥ 40,000$ increase

B) $¥ 20,000$ increase

C) $¥ 40,000$ decrease

D) $¥ 20,000$ decrease