The file command determines the type of a file by using a definition database file which contains information about all common file types. The database file is usually located at /usr/share/misc/magic or /usr/share/file
/magic and can be customized by the user. The file command analyzes the content and structure of the file and compares it with the patterns in the database file to identify the file type. The file command can also check the file name extension, but it does not rely on it. The other options are either invalid or do not perform the desired task. The magic, pmagic and hash commands are not valid Linux commands. The type command is used to display information about command type, not file type. References:
* LPIC-1 Exam 101 Objectives, Topic 103: GNU and Unix Commands, 103.3 Perform basic file management
* LPIC-1 Linux Administrator 101-500 Exam FAQ, LPIC-1 Exam 101 Objectives, GNU and Unix Commands (Total Weight: 25)

The tail command prints the last part of a file to the standard output. The -n option specifies the number of lines to print. Therefore, tail -n 10 filename will print the last 10 lines of the file named filename. The other commands are either invalid or do not perform the desired task. The cat command concatenates files and prints them to the standard output, but it does not have a -n option. The dump command is used to backup filesystems, not to print files. The head command prints the first part of a file, not the last part. References:
* LPIC-1 Exam 101 Objectives, Topic 103: GNU and Unix Commands, 103.3 Perform basic file management
* LPIC-1 Linux Administrator 101-500 Exam FAQ, LPIC-1 Exam 101 Objectives, GNU and Unix Commands (Total Weight: 25)

dpkg-reconfigure
Explanation:
The dpkg-reconfigure command is used to reconfigure an already installed package. It asks configuration questions for the package, just as if the package were being installed for the first time. This can be useful if the user wants to change some settings or options for the package without reinstalling it. The dpkg- reconfigure command can also be used to fix a broken package configuration or to restore the default settings.
References:
* dpkg-reconfigure(8) - Linux man page
* Linux Professional Institute: Exam 101 Objectives

The dd command is used to copy data from one device or file to another, with optional parameters to specify the block size (bs), the number of blocks to copy (count), and other options. The bootloader is typically located in the first 440 bytes of the disk, which is the Master Boot Record (MBR) area. The MBR also contains the partition table, which starts at byte 446 and occupies 64 bytes. Therefore, to overwrite the bootloader without affecting the partition table or any data following it, the command should copy 440 bytes from /dev/zero (a special device that provides null bytes) to /dev/sda (the disk device) and stop after one block. This is achieved by the command: dd if=/dev/zero of=/dev/sda bs=440 count=1 References:
* LPI Exam 101 Detailed Objectives, section 1.101.3
* dd man page
* Master Boot Record

The command dd can be used to create a USB storage media from a disk image. The command dd is a low- level utility that can copy and convert data from one source to another, such as files, devices, or pipes. It can be used to create a bootable USB drive from an ISO image or a raw disk image. The syntax is: dd if=input of=output [options]. For example, to create a USB storage media from a disk image file named linux.img, the command would be:
dd if=linux.img of=/dev/sdb
This will copy the contents of linux.img to the device /dev/sdb, which is assumed to be the USB drive. The device name may vary depending on the system, so it is important to check the correct device name before running the command. The command dd can also accept various options, such as bs to specify the block size, status to show the progress, or conv to apply conversions to the data. For example, to create a USB storage media from an ISO image file named linux.iso, with a block size of 4 MB and a progress indicator, the command would be:
dd if=linux.iso of=/dev/sdb bs=4M status=progress
The command dd is also known as "disk destroyer" because it can overwrite data without warning or confirmation. Therefore, it is advisable to use it with caution and backup any important data before using it.
The other options are not correct because:
* gdisk is a command to create and manipulate GUID partition tables (GPT), but it does not create a USB storage media from a disk image1.
* cc is a command to compile C programs, but it does not create a USB storage media from a disk image2.
* fdisk is a command to create and manipulate DOS partition tables, but it does not create a USB storage media from a disk image3.
* mount is a command to mount file systems, but it does not create a USB storage media from a disk image4. References:
* How to Create a Bootable Linux USB Flash Drive, the Easy Way
* dd(1) - Linux manual page
* How to use the dd command in Linux - TechRepublic
* LPI Exam 101 Detailed Objectives, section 1.101.3