Based on the tests in $($a$)$ to $($d$),$ determine which of the presented statements represent appropriate items to be included on a memo assessing the results of tests of controls. $($Select all items that apply in the list below by choosing $"$X$"$ in the corresponding cell in dropdown column. For items that do not apply, leave the corresponding dropdown cell blank.$)$

Statements

Controls surrounding the existence and completeness assertions of customer orders may be reasonably relied on$.$

Multiple violations of authorization controls increases our assessment of control risk for the valuation of accounts receivable.

ELM's timely invoicing of customers reduces control risk for the completeness and cutoff assertions of sales revenue.

Duplicate customer order numbers indicate potential control deficiencies related to the occurrence assertion of sales revenue.