Q
Which attribute should be used for loading external JavaScript files without blocking rendering in the <head> or <body> sections?

Answer & Solution

Answer: Option B
Solution:
The defer attribute is used to load external scripts asynchronously without blocking rendering, ensuring that HTML parsing and rendering are not delayed due to script loading and execution. The async attribute also loads asynchronously but doesn't guarantee execution order, which makes defer more suitable for scripts that depend on order.
Related Questions on Average

Using the defer attribute with an external script in the <head> section means that the script:

A). Loads and executes after HTML parsing.

B). Loads synchronously with HTML parsing.

C). Loads and executes before HTML parsing.

D). Loads but doesn't execute.

When using an external JavaScript file in the <head> section with the defer attribute, when does it get executed?

A). After the HTML content is fully parsed.

B). Before the HTML content is parsed.

C). As soon as it starts loading.

D). After all other scripts in the <head>.

Using the defer attribute with an external JavaScript file in the <body> section means that the script:

A). Loads and executes after HTML parsing.

B). Loads synchronously with HTML parsing.

C). Loads and executes before HTML parsing.

D). Loads but doesn't execute.

Variables declared in the <body> section of an HTML document have what scope by default?

A). Local to the script or function.

B). Global throughout the document.

C). Limited to the <body> section.

D). Not accessible in JavaScript.

Placing JavaScript at the end of the <body> section is beneficial for:

A). Improving page load speed.

B). Blocking page rendering.

C). Increasing script complexity.

D). Hiding script functionalities.

Variables declared in the <head> section of an HTML document are accessible:

A). Globally throughout the document.

B). Only within the <head> section.

C). Only after the page has fully loaded.

D). Nowhere in the document.

What is the purpose of using the async attribute with an external JavaScript file?

A). To load the script asynchronously.

B). To defer script execution.

C). To block rendering until script loads.

D). To ensure script execution order.

What happens if JavaScript code in the <head> section of an HTML document is not properly handled?

A). It may block rendering and cause delays.

B). It automatically moves to the <body>.

C). It gets executed twice.

D). It has no impact on the page.

When JavaScript is placed in the <head> section of an HTML document, it can:

A). Execute before page rendering.

B). Execute after page rendering.

C). Block rendering until execution.

D). None of the above.

Which of the following is a recommended practice for optimizing JavaScript performance?

A). Minify and concatenate scripts.

B). Include all scripts in the <head>.

C). Use synchronous loading for all scripts.

D). Load scripts without optimization.