The shell redirection that will write standard output and standard error output to a file named filename is
>filename 2>&1. This command uses the following syntax:
* filename: Redirects standard output (file descriptor 1) to a file named filename. If the file does not exist, it will be created. If the file exists, it will be overwritten.
* 2>&1: Redirects standard error (file descriptor 2) to the same destination as standard output. The & symbol indicates that the following number is a file descriptor, not a filename.
The order of the redirections is important, as they are processed from left to right. If the order was reversed, as in 2>&1 >filename, the command would not work as expected, because it would first redirect standard error to the current standard output (which is the terminal by default), and then redirect standard output to the file, leaving standard error unchanged.
The other commands are incorrect for the following reasons:
* A. 2>&1 >filename: This command will redirect standard error to the current standard output, and then redirect standard output to the file, leaving standard error unchanged.
* C. 1>&2>filename: This command will redirect standard output to the current standard error, and then redirect standard error to the file, leaving standard output unchanged.
* D. >>filename: This command will only redirect standard output to the file in append mode, without affecting standard error.
* E. 1&2>filename: This command is not valid, as it is missing the > symbol before the first file descriptor, and it will produce an error message.
References:
[LPI Exam 101 Detailed Objectives], Topic 103: GNU and Unix Commands, Objective 103.4: Use streams, pipes and redirects, Weight: 4, Key Knowledge Areas: Redirecting standard input, standard output and standard error.
How to redirect and append both standard output and standard error to a file with Bash, Topic: Substituting Text.

The command that is used to change options and positional parameters for a running Bash is set. The set command allows the user to modify the behavior of the shell by enabling or disabling various options, such as
-x (trace mode), -e (exit on error), -u (treat unset variables as errors), and others. The set command can also be used to assign values to the positional parameters, which are the arguments passed to the shell or a shell script. The positional parameters are denoted by $1, $2, $3, and so on, up to $9. The special parameter
0referstothenameoftheshellortheshellscript.Thespecialparameter# refers to the number of positional parameters. The special parameter $@ refers to all the positional parameters as a list.
To change the positional parameters, the set command can be used with the - option, followed by the new arguments. For example, the following command will set the positional parameters to "a", "b", and "c":
set - a b c
After this command, $1 will be "a", $2 will be "b", 3willbe"c",# will be 3, and $@ will be "a b c". The - option signals the end of options and prevents any argument that starts with a - from being interpreted as an option. Alternatively, the set command can be used with the - option, followed by the new arguments.
However, this will also disable the -x and -v options, if they were previously enabled. For example, the following command will set the positional parameters to "-a", "-b", and "-c", and turn off the trace and verbose modes:
set - -a -b -c
The set command can also be used without any option or argument, in which case it will display the names and values of all shell variables and functions.
The other commands are not valid or relevant for changing options and positional parameters for a running Bash. The history command displays the history list of commands entered by the user. The bashconf command does not exist. The setsh command does not exist. The envsetup command does not exist.
References:
[LPI Exam 101 Detailed Objectives], Topic 103: GNU and Unix Commands, Objective 103.1: Work on the command line, Weight: 4, Key Knowledge Areas: Use of set and unset.
[Bash Reference Manual], Section 4.3: The Set Builtin.

The files that exist in a standard GRUB 2 installation are /boot/grub/i386-pc/1vm.mod and /boot/grub/grub.
cfg. The /boot/grub/i386-pc/1vm.mod file is a GRUB 2 module that provides support for the 1vm command, which allows loading a virtual machine image from a disk1. The /boot/grub/grub.cfg file is the main configuration file for GRUB 2, which contains the menu entries and options for the bootloader2. The other files are either non-existent or do not belong to GRUB 2. The /boot/grub/stages/stage0 file is part of the GRUB legacy bootloader, which used a different architecture and naming scheme than GRUB 23. The /boot
/grub/fstab file is not a valid file name, as fstab is the name of the file system table file that is usually located in /etc directory4. The /boot/grub/linux/vmlinuz file is also not a valid file name, as vmlinuz is the name of the compressed Linux kernel image that is usually located in /boot directory5. References:
* GRUB 2 bootloader - Full tutorial - Dedoimedo1
* Grub2/Installing - Community Help Wiki - Official Ubuntu Documentation2
* GRUB bootloader - Full tutorial - Dedoimedo3
* fstab(5) - Linux manual page4
* vmlinuz(5) - Linux manual page5