A company serves static content using a global HTTP(S) load balancer with Cloud CDN. They want to maximize the cache hit ratio. Which two actions should they take?
A long max-age allows content to be cached for a year, maximizing cache hits.
Why this answer
Setting Cache-Control: public, max-age=31536000 instructs browsers and intermediate caches to store the response for one year, maximizing the likelihood that subsequent requests are served from cache. This long max-age reduces the need for revalidation, directly improving cache hit ratio.
Exam trap
Google Cloud often tests the misconception that signed URLs or IAP improve caching, when in fact they introduce per-request variability that reduces cache hit ratio, and that Cache-Control: private is appropriate for static content when it actually prevents caching entirely.