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

Answer & Solution

Answer: Option A
Solution:
An external JavaScript file in the <head> with the defer attribute gets executed after the HTML content is fully parsed, ensuring that it doesn't block rendering or delay the display of core page content to users.
Related Questions on Average

Placing JavaScript at the end of the <body> section of an HTML document can result in:

A). Faster initial page rendering.

B). Slower overall page loading.

C). No impact on page performance.

D). Delayed execution of JavaScript.

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.

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.

How can JavaScript be loaded asynchronously in the <body> section without blocking page rendering?

A). Using the defer attribute.

B). Using the async attribute.

C). Including scripts in the <head>.

D). Not possible in the <body>.

Which attribute can be used to make external JavaScript files load asynchronously in the <head> or <body> sections?

A). async

B). defer

C). sync

D). load

Which scenario is suitable for placing JavaScript in the <head> section of an HTML document?

A). Initializing variables or configurations.

B). Dynamic content manipulation.

C). User interaction scripts.

D). External script loading.

What happens if JavaScript code in the <body> section of an HTML document is placed before critical content such as headings or main paragraphs?

A). It may cause FOUC (Flash of Unstyled Content).

B). It has no effect on page rendering.

C). It improves page load speed.

D). It slows down script execution.

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.

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.

Placing JavaScript in the <head> section can impact page load times because:

A). It blocks rendering until executed.

B). It loads scripts asynchronously.

C). It reduces HTTP requests.

D). It has no impact on loading.