Boomerang Computer Company sells computers with an unconditional right to return the computer if the customer is not satisfied. Boomerang has a long history selling these computers under this returns policy and can provide precise estimates of the amount of returns associated with each sale. Boomerang most likely should recognize revenue:

When Boomerang delivers a computer to a customer, ignoring potential returns.

When Boomerang delivers a computer to a customer, in an amount that is reduced by the expected returns.

When Boomerang receives cash from the customer.

When a customer returns a computer.