Sequential codes are applied primarily to source documents such as...........

Cheque

The correct answer is option 2- Cheque.

Sequential codes are applied primarily to source documents such as Cheque.

In Sequential Code, numbers and/or letters are assigned in consecutive order. These codes are applied primarily to source documents such as cheques, invoices, etc. A sequential code can facilitate document searches. This process enables in either identification of missing codes (numbers) relating to a particular document or a relevant document can be traced on the basis of code.