What is a reason to set the insert options on a specific item under the content node of the content tree?

[answerhappygod]

What is a reason to set the insert options on a specific item under the content node of the content tree?

A. To allow Content Authors to insert items into the content tree for all the templates they have access to
B. To allow Content Authors to insert items under the specific item in addition to what is included with the item's standard values
C. To allow Content Authors to insert new items under any item within the content tree
D. To allow Content Authors to insert items created from any system template into the content tree under the specific item