c, f and g are all invalid and produce compiler messages.  If we
put all of them in as successive statements, we get:

NAG Fortran Compiler Release 5.2(668)
Error: ex_10.1.2.f90, line 4: Syntax error
       detected at ,@*
***Malformed statement
Error: ex_10.1.2.f90, line 8: Syntax error
       detected at ,@*
***Malformed statement
[NAG Fortran Compiler pass 1 error termination, 2 errors]

If we now remove c and g (lines 4 and 8), we get:

NAG Fortran Compiler Release 5.2(668)
Error: ex_10.1.2.f90, line 6: Unit-specifier occurs twice in io-control-spec-list
[NAG Fortran Compiler error termination, 1 error]

If we now remove f (line 6), we get:

 Abc   1.2300000E-06 -456 xyz
 Abc   1.2300000E-06 -456 xyz
 Abc   1.2300000E-06 -456 xyz
 Abc   1.2300000E-06 -456 xyz

So the remainder are all equivalent to the PRINT statement.