Each string literal is automatically added with a ........... terminating character.

Question

Accepted Answer

The correct option is (1):
The fundamental characteristic of a string literal in languages like C and C++ is that it is automatically terminated by a **null character**, often written as the escape sequence $\text{'\textbackslash} 0'$ or simply represented by the decimal value 0. While the literal text provided in Option (1) is inconsistent with the standard C/C++ notation for the null character, we must understand that this option refers to the concept of the null-terminating character, which is crucial for defining the end of a string in memory. The null character holds the integer value 0, and all standard library functions (like $\text{strlen}$, $\text{strcpy}$, $\text{printf}$) rely on this null terminator to correctly identify where a string ends. Without this automatic addition of $\text{'\textbackslash} 0'$ by the compiler, string handling operations would not know how to process the entire sequence of characters.

The incorrect option is (2):
Option (2), the string literal $\text{\text{''}}11\text{\text{''}}$, is incorrect because this sequence of characters has no special, universally recognized significance as a string terminator. The characters '1' and '1' are regular, printable data characters. If the string ended with "11", the actual null character ($\text{'\textbackslash} 0'$) would appear *after* the '11' in memory, meaning '11' is part of the data. A true terminator must be a single, non-printable character that signals the absolute end to all string-processing routines. Using a multi-character sequence like $\text{\text{''}}11\text{\text{''}}$ as a terminator is non-standard and would waste memory.

The incorrect option is (3):
The string literal $\text{\text{''}}\text{\#}\text{\text{''}}$ is simply the pound or hash symbol, which is a regular, printable character. If the compiler used $\text{\text{''}}\text{\#}\text{\text{''}}$ as the automatic terminator, any string that legitimately contained the '\#' character would be prematurely terminated when processed by a string function, leading to data loss or errors. For example, the string "Part \#1" would be incorrectly treated as just "Part ". The null character is the chosen standard because its value of 0 is guaranteed not to appear in string data, thereby creating an unambiguous end marker.

The incorrect option is (4):
The notation $\text{\#0'}$ is not a standard C/C++ notation for a string terminator. The correct representation of the null character as a single-character literal is $\text{'\textbackslash} 0'$, which is a special escape sequence representing the character with an integer value of 0. This option's convoluted and syntactically non-standard nature clearly indicates it is not the correct, standard-compliant answer for the automatically appended string terminating character.