Which of the following is a micro-optimization that modern JavaScript engines can typically handle better without manual intervention?
Manually inlining small functions is a micro-optimization that modern JavaScript engines (like V8, SpiderMonkey, or JavaScriptCore) typically handle better through their Just-In-Time (JIT) compilation process. These engines can automatically inline functions when beneficial based on runtime analysis. The other options listed are still valid optimizations in many cases: for..of loops can be faster than forEach for simple operations, caching property lookups avoids repeated object access overhead, and array literals are generally preferred over the constructor syntax for clarity and performance. Focus on writing clean, maintainable code and optimizing the algorithmic complexity rather than these micro-optimizations in most cases.