Simplify this into one sentence only

How can I simplify this into one sentence in vba?

 If [BT12] = "a" Then
   Range("AB12").ClearContents
 End If

 If [BT13] = "a" Then
   Range("AB13").ClearContents
 End If

 If [BT14] = "a" Then
   Range("AB14").ClearContents
 End If