What is the output of the following snippet of code?

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#include <stdio.h>
int* inc(int val)
{
    int a = val;
    a++;
    return &a;
}
int main(void)
{
    int a = 10;
    int *val = inc(a);
    printf("\n Incremented value is equal to [%d] \n", *val);
    return 0;
}

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Answer: C. Runtime Error

The function inc() returns a pointer to a local variable a, which ceases to exist when the function returns. Dereferencing this dangling pointer in main() results in undefined behavior—typically a runtime error or garbage value. While the code compiles successfully, accessing the invalid memory address at runtime causes a crash or unpredictable output.

Step-by-step Derivation:
Step-by-step analysis:

inc(10) is called: local variable a is created on the stack, incremented to 11.
Function returns &a—the address of the local variable.
When inc() returns, a goes out of scope and its memory is reclaimed/no longer guaranteed to be valid.
In main(), *val dereferences a dangling pointer (points to freed/invalid stack memory).
Accessing this memory at runtime causes undefined behavior: typically a segmentation fault or runtime error.
The code compiles without error because the syntax is valid, but execution fails due to illegal memory access.

What is the output of the following snippet of code?

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