A company requires assistance with the program checks that will ensure compliance with the requirements below pertaining to the accuracy and completeness of the online input of sales invoice data. The following is a list of requirements for the companys tax invoices: $1)$ Sales invoices should be issued only to clients with a valid account number. $2)$ The minimum number of a specific item that may be purchased is one and the maximum number is $20.3)$ The percentage of VAT for all non exempt items on the invoice should be $15\%4)$ Invoices should be issued in numerical sequence. Which ONE of the following alternatives $($a$,$ b$,$ c or d$)$ matches the invoice requirements described in $1)$ to $4)$ above with the correct program check that will ensure that the requirements are met?a$.$ Mandatory fields, Check digit, Sequence check, Range checkb. Sequence check, Sequence check, limit check, Mandatory fieldsc. Range check, limit check, mandatory fields, sequence check d$.$ check digit, range check, limit check, sequence check