%d specifier display the output in decimal number system. 56 is the decimal number, 056 is the octal number equivalent to 46 in decimal, 0x56 is the hexadecimal number equivalent to 86 in decimal. So, the output will be 56 46 86.

%c specifier prints C because 'C' is a character. But %d specifier prints 67 (ASCII value of C).

Range of int is -32768 to +32767. Value of m exceeds the limit of int. So after 32767, it goes to the other side of the range and 32769 will convert to -32767. Range of unsigned int is 0 to 65535. Value of n exceeds the limit of int. So after 65535, it goes to the other side of the range and 65535 will convert to 4.

Range is not wraps around in case of float datatype. So, if float value is outside the range on +ve side, then output will be +INF (+ infinity).

Keywords cannot be identifier.

'short' is the type modifier. Type modifier modifies the range and the properties of base type.

Space is not allowed in variable name. For example, RollNum is valid and Roll Num is invalid variable name.

Initially C language was intended for the system programming. For example, UNIX operating system is written in C language.

%x is the format specifier, which is used for printing an unsigned integer in hexadecimal number system. %h is not a valid format specifier. %u is used for printing the unsigned integer in decimal number system. %hd is used for printing the signed short.

If any integer data type uses n bytes, then its maximum range will be 2^{(No of bits -1)}-1. In this case, 2 Bytes = 16 bits 2^(16-1) - 1 = 2¹⁵-1=32768-1=32767

String constant uses 1 byte for each character and 1 byte for the null character at the end of the string. So, number of character in “abcdefdgi” is 9, and 1 null character is at the end of string, i.e. 10.

sizeof('9') gives 1 because '9' is a character not integer and sizeof(567) gives 2 because 567 is an integer.

All of these are the characteristics of Variable. Variables must have its name, data type and value. Without data type variables cannot be declared. Variables also have some location in memory. And variables' value can be changed during the execution of a program.

The extern storage class declared the variable as an external variable, which can be accessed from any part of the program.

Auto is the default storage class in C language. For example: auto int num;  or int num; Both of the above statements are the same.

stdio.h is used for the standard input/output. assert.h contains the assert(). alloc.h contains the malloc(), calloc(), realloc() etc. malloc.h is not a header file.

All structure, function and arrays are the derived data types. Derived data types are derived from base data type.

There are 32 keywords in C language.

It will print 1 because ' ' is a tab character. ' ' is the escape sequence and C language considers all escape sequence as a single character.