lengthy web pages have proven to be which of the following?\nsuccessful at selling products\nless…

Brief Explanations:

Online readers often prefer concise content. Lengthy web - pages tend to be discouraging as they require more time and effort to read through. They are not necessarily successful at selling products, may not be less informational than customer service representatives, and being written in common language doesn't guarantee their effectiveness if they are too long.

Answer:

Discouraging to online readers