Why is the answer D?

Undersea Construction Ltd commenced the construction of a tunnel under a major river for public transport on 1 July 20X4. It has a fixed-price contract for total revenues of $36 million. The expected completion date is 30 June 20X7. The expected total cost to Undersea Construction at the beginning of the project is $27 million. The following information relates only to the construction of the tunnel: 20X5 20X6 20X7 For the year ending 30 June $'000 $'000 $'000 Costs for the year 5,000 15,000 10,000 Costs incurred to date 5,000 20,000 30,000 Estimated costs to complete 22,000 8,500 Progress billings during the 10,000 22,000 4,000 year Cash collected during the year 9,000 19,000 8,000 Undersea Construction uses the percentage of completion method based on cost to account for its construction contracts. All cost estimates are reliable. 10. If in 20X6, the estimated costs to complete are $18,000 (not $8,500) and the $18,000 cost is indeed incurred in 20X6, the gross profit or loss reported each year by Undersea Construction on this construct will be: (in $'000s) 20X5 20X6 20X7 a) $3,596 $2,000 (loss) $8.000 b) $1,667 $2,000 (loss) $zero c) $3,576 $5,833 $zero d) $1,667 $3,867 (loss) $zero e) $1,667 $3,867 (loss) $4,000