Which statement is false?

Correct option is C

Option (a): True. In C, all function calls pass arguments using call by value, meaning a copy of the value is passed to the function. Changes made to the parameter inside the function do not affect the original argument.
Option (b): True. Call by reference enables modifying a variable in the calling function by passing the address of the variable, allowing the function to directly manipulate the original value.
Option (c): False. Call by value is not always more efficient than call by reference. Passing large data structures or arrays by value creates a copy, consuming more memory and time. In contrast, call by reference passes only the address, which is more efficient in such cases.
Option (d): True. In C, pointers and indirection operators simulate call by reference, allowing direct modification of variables in the calling function.
Thus, the false statement is Option (c).
Information Booster:
1. Call by Value:
· A copy of the actual argument is passed to the function.
· Modifications inside the function do not affect the original variable.
· Safer as it protects the original data but less efficient for large data structures.
2. Call by Reference:
· The address of the variable is passed to the function.
· Enables modification of the original data.
· More efficient for large structures or frequent data manipulations but requires careful handling to avoid unintended changes.
3. Simulating Call by Reference in C:
· Use pointers to pass the address of variables.
· Example:
void modify(int *x) {
*x = 10;
}
4. Efficiency Consideration:
· Small data types (e.g., integers, floats) are faster with call by value.
· Large data types (e.g., arrays, structs) are more efficient with call by reference.
Additional Knowledge:
· Pointers in C:
· Enable dynamic memory allocation.
· Facilitate efficient function calls and memory management.
· Drawbacks of Call by Reference:
· Potential for unintentional changes to the original data.
· More complex to implement due to pointer usage.