Correct choice is (d) @import
Easy explanation: Within embedded <style> blocks, properties can be imported from an external file and expanded in place, similar to a macro. Importing can be used to include multiple style sheets. An imported style is defined within a <style> tag using @import followed optionally by a type value and a URL for the style sheet. <style> & <script> tag conatins CSS and Javascript content respectively. The metadata content is present in <head> tag.
