Computer Science

The HTML tag used to underline text is the <u> tag. This tag encloses the text you want to underline, for example: <u>underlined text</u>. While the <u> tag was deprecated in HTML 4, it was reintroduced in HTML5 with a semantic meaning related to non-textual annotations. However, it still renders text with an underline by default in all modern browsers. The <underline> tag is not a valid HTML tag, and option B is invalid. Therefore, the correct answer is C.

Twitter was launched in March 2006, making option A the correct answer. This is a well-documented fact in the history of social media platforms.

The Internet is commonly referred to both as "The network of networks" because it connects multiple networks worldwide, and informally as "The net." Therefore, option C, "Both," is correct.

IC stands for Integrated Circuit, which is a set of electronic circuits on a small chip of semiconductor material, commonly used in electronic devices.

Among the options given, GB (Gigabyte) is the largest unit of memory. KB (Kilobyte) is smaller than MB (Megabyte), and MB is smaller than GB. Larger units such as Terabyte (TB) and beyond exist, but since they are not listed in the options, the largest unit among the given choices is GB.

Ctrl + Z is the standard keyboard shortcut used to undo the last action in most software applications, making option B the correct answer.

A bit is the smallest unit of data in computing and represents a binary value of either 0 or 1. It is not equal to any decimal number like 0.125, 0.150, or 0.12, so the correct answer is 'None of these'.

Microsoft released the first version of Windows, Windows 1.0, in 1985. Therefore, option A is correct.

Floppy disk drives, hard disk drives, and optical disk drives can both read data (input) and write data (output), making them both input and output devices. Teleprinters also function as both input and output devices, as they can send and receive data. Therefore, the correct answer is 'Both A and B'.

LCD stands for Liquid Crystal Display, which is a flat-panel display technology commonly used in monitors, televisions, and other screens. The other options are incorrect expansions of the acronym.