subroutine call_option(option, arg_pos)
    use parameters
    use opt_disl
    use opt_group
    use opt_orient
    use opt_delete
    use box
    implicit none

    integer, intent(inout) :: arg_pos
    character(len=100), intent(in) :: option

    select case(trim(adjustl(option)))
    case('-dislgen', '-disloop','-vacancydisloop')
        call dislocation(option, arg_pos)
    case('-group')
        call group(arg_pos)
    case('-ow')
        arg_pos = arg_pos + 1
    case('-wrap')
        arg_pos = arg_pos + 1
    case('-orient')
        call orient(arg_pos)
    case('-unorient')
        call unorient
        arg_pos = arg_pos + 1
    case('-boundary')
        arg_pos=arg_pos+1
        call get_command_argument(arg_pos, box_bc)
        arg_pos=arg_pos+1
        bound_called = .true.
    case('-delete')
        call run_delete(arg_pos)
    case default
        print *, 'Option ', trim(adjustl(option)), ' is not currently accepted.'
        stop 3 
    end select
end subroutine call_option