who is giving advice to a colleague. She tells the colleague that all of the following are essential to implement online transactions, except:

Helga is an e-commerce developer who is giving advice to a colleague. She tells the colleague that all of the following are essential to implement online transactions, except:

A.
Performing routine systems maintenance

B.
Preparing the server and e-commerce site

C.
Setting up an online merchant account

D.
Installing payment software