Which of the following networks has the LEAST likelihood of collisions?

When a Radio Button or a Check Box control’s Checked property changes, a ____________ happens for that control.

a. Selection Changed event b. Checked event c. Check Changed event d. Click event

On a working network, the software that users employ when accessing the network resides at Layer ______________ in the OSI seven-layer model.

Fill in the blank(s) with the appropriate word(s).