CASE equivalent of a nested IIF statement

Question

Can anyone please decode the following nested IIF to a CASE statement in SQL.. I know IIF is allowed in SQL Server 2012 but I find it hard to get an easy grasp of a nested IIF l

Answer 1

CASE 
    WHEN 
     (CASE 
          WHEN TABLE_A.Col1= 0 
          THEN TABLE_A.Col2_2 + (2*TABLE_A.Col3)
          ELSE TABLE_A.Col1 
      END) <=0.5 
    THEN 'A'
    ELSE 'B'
END
AS result