Joe is an auditor who is at an audit engagement at a large convenience store chain in New York City. During his audit, he notices that the invoices are not pre$-$numbered, but instead are printed on blank sheets of paper. At the cash registers, Joe notices that one employee does all of counting the cash in the register, journalizing the sales, and making the deposit at the bank.

Which internal control principle$($s$)$ has$($have$)$ been violated?

a$.$

documentation procedures

b$.$

Both segregation of duties and establishment of responsibility

c$.$

establishment of responsibility

d$.$

Both segregation of duties and documentation procedures