If Column C contain "100" then Column D should update "001

Someone please help me to create a VBA Code. If Column C contain "100" then Column D should update "001"If Column C Contain "101" then Column D should update "002". This is required for selective cell range in column C. I am trying to prepared code as below but its does not working.

Sub iflocation()
If activecell.Range("c1:C").Value = 100 Then Range("d1"d").Value = Range "001.Value
If activecell.Range("c1:C").Value = 101 Then Range("d1"d").Value = Range "002.Value
End sub