Choice "A" is correct. When there is an unlimited right of return, nothing should be recorded as sales revenue unless four conditions are satisfied. These conditions are the following:

• The sales price is substantially fixed (it seems like it is in this question).

• The buyer assumes all risk of loss (no information).

• The buyer has paid some form of consideration (no information).

• The amount of returns can be reasonably estimated (which they can in this question).

Because all four conditions have not been satisfied, revenue should not be recognized until they are or until something is actually sold.Choice "b" is incorrect. No revenue should be recognized because all four conditions have not been satisfied.
Choice "d" is incorrect. No revenue should be recognized because all four conditions have not been satisfied.
Choice "c" is incorrect. No revenue should be recognized because all four conditions have not been satisfied.