Next.js MCQs - Data Fetching, Caching, ISR and Server Actions (Set 5)

Q1. In the App Router, which function lets you pre-render dynamic route segments such as /blog/[slug] at build time?

a) generateMetadata

b) getStaticPaths

c) generateStaticParams

d) getServerSideProps

Q2. What does the following export in app/blog/page.tsx do?

export const revalidate = 60;

export default async function BlogPage() {
  const posts = await getPosts();
  return <PostList posts={posts} />;
}

a) Caches the page and regenerates it in the background at most once every 60 seconds when it is requested

b) Forces the page to render on every request

c) Delays the response by 60 seconds

d) Rebuilds the whole site every 60 seconds

Q3. In Next.js 15, how are fetch requests inside Server Components cached by default?

a) They are cached for exactly 60 seconds

b) They are cached only in the browser

c) They are cached forever

d) They are not cached by default unless you opt in, for example with cache: 'force-cache'

Q4. After a user submits a form that adds a new blog post, which function can you call to purge cached data for the /blog route?

a) router.refresh() on the server

b) revalidatePath('/blog')

c) useEffect

d) generateStaticParams

Q5. How do you attach a cache tag to a fetch request so it can be revalidated later with revalidateTag('posts')?

a) fetch(url, { tag: 'posts' })

b) fetch(url, { next: { tags: ['posts'] } })

c) fetch(url, { cache: 'posts' })

d) fetch(url).tag('posts')

Q6. Using cookies() or headers() inside a Server Component usually makes the route:

a) Fail during the build

b) Run only on the client

c) Statically rendered at build time

d) Dynamically rendered at request time

Q7. Which directive marks a function as a Server Action that can be called from a form or a Client Component?

a) 'use server'

b) 'use action'

c) 'use strict'

d) 'use client'

Q8. What is a loading.tsx file in a route segment used for?

a) Defining API routes

b) Preloading images

c) Showing an instant loading UI, wrapped in a Suspense boundary, while the segment's content streams in

d) Loading environment variables

Q9. Why must an error.tsx file be a Client Component?

a) Because Server Components cannot render text

b) It does not need to be

c) Because errors cannot happen on the server

d) Because it is built on a React error boundary and receives a reset function to retry rendering

Q10. Which file creates an API endpoint inside the app directory?

a) route.ts

b) handler.ts

c) server.ts

d) api.ts

Q11. getServerSideProps belongs to which part of Next.js?

a) next.config.js

b) The App Router

c) The Pages Router

d) Middleware

Q12. What is generateMetadata mainly used for?

a) Generating TypeScript types

b) Creating dynamic SEO metadata such as title, description and Open Graph tags based on route params or fetched data

c) Generating sitemaps automatically

d) Creating static params

Q13. Which of these is NOT a built-in benefit of the next/image component?

a) Automatically writing alt text for the image

b) Lazy loading by default

c) Serving resized images in modern formats such as WebP

d) Avoiding layout shift by reserving space

Q14. What is middleware (renamed to proxy in Next.js 16) commonly used for?

a) Bundling CSS

b) Replacing the database layer

c) Rendering React components

d) Running logic such as auth checks, redirects, rewrites or setting headers before a request reaches a route

Q15. What happens when you call notFound() from next/navigation in a Server Component?

a) The page silently renders nothing

b) The app crashes

c) Rendering stops and the nearest not-found.tsx UI is shown with a 404 status

d) The user is redirected to the home page