Minimum number of functions in a C program

In C programming language, a function is a self-contained block of code that performs a specific task. Functions are essential for organizing and modularizing code, and they are necessary for the execution of a C program.

Answer:
The correct answer is option 'B' - 1.

Explanation:
A minimum of one function should be present in a C program for its execution. This function is known as the main function. The main function is the entry point of a C program, and it is where the program execution starts.

The main function has a specific syntax and structure in C:

```
int main() {
// Code statements
return 0;
}
```

Inside the main function, you can write the code statements that define the behavior of your program. These statements can include variable declarations, calculations, input/output operations, and function calls.

The main function must have a return type of `int`, which indicates the status of the program execution. A return value of 0 usually indicates successful execution, while non-zero values indicate some error or abnormal termination.

Optional Additional Functions:
Although a C program can technically execute with just the main function, it is common to have additional functions in the program to perform specific tasks. These functions can be defined before or after the main function.

Having additional functions allows for code organization, reusability, and modularity. Functions can be called from within the main function or from other functions, enabling the program to perform complex operations by dividing them into smaller, manageable tasks.

Conclusion:
While a minimum of one function (the main function) is required for a C program's execution, additional functions can be included to enhance code structure and functionality. However, the main function is essential and serves as the entry point for the program.