Which of the following is NOT a standard operation step in a Programmable Logic Controller (PLC) cycle?

A PLC ladder logic program has two parallel rungs containing contacts A and B, which are in series with another contact D. This entire combination is in series with a contact C. Which Boolean function represents this program?

The ___________ operation in a Programmable Logic Controller (PLC) means that the output is ON if at least one of the inputs is ON; it is analogous to relay contacts connected in parallel.