The correct answer is Line 20 (Negotiable Instruments).
US Treasury checks are considered negotiable instruments, which are financial instruments that can be easily transferred from one person to another. As such, they are recorded on line 20 of the DD Form 2665.
Line 17 (Cash On Hand) is used to record cash that is physically on hand, such as coins and bills. Line 23 (Paid Voucher) is used to record vouchers that have been paid, such as invoices or receipts.
Here is a table that summarizes the different types of transactions that are recorded on each line of the DD Form 2665:
Line Description
20 Negotiable instruments, such as US Treasury checks
17 Cash on hand
23 Paid vouchers
Complete question:
What line on the DD Form 2665 will a deputy or agent enter a US Treasury check cashed?
Line 20 (Negotiable Instruments)
Line 17 (Cash On Hand)
Line 23 (Paid Voucher)