Tab Controls effecting other Controls

Hopefully I've explained myself good enough this time. Can't seem to get a real answer. Trying to make it so 开发者_运维知识库when I select certain tabs, certain controls on the left will disappear or reappear.

http://img43.imageshack.us/img43/7533/scrnshotg.jpg

Also, when "Stats" is selected, I need it to auto-select "Frequency"

Ex. On click/focus/select (whatever, nothing seems to work)... ComboBox.Visible = True

Thank you.

Handle the TabControl.TabIndexChanged event.

http://msdn.microsoft.com/en-us/library/system.windows.forms.control.tabindexchanged%28v=VS.100%29.aspx