You're reviewing a C++ codebase and notice that a function processing large data structures is passed its arguments by value, potentially causing unnecessary copies and overhead. What might be a more efficient way to pass these structures without modifying the original data? 

Passing arguments by reference allows functions to access the original memory location without creating a copy, leading to more efficient memory usage. While passing by pointer can achieve a similar outcome, it requires manual dereferencing. Passing by reference is a more idiomatic solution in C++ for this use case.