The duality of effects can best be described as follows:

a. When a transaction is recorded in the accounting system, at least two effects on the basic accounting equation will result.
b. When an exchange takes place between two parties, both parties must record the transaction.
c. When a transaction is recorded, both the balance sheet and the income statement must be impacted.
d. When a transaction is recorded, one account will always increase and one account will always decrease.