The tags are always enclosed within a pair of
(a) curly
(b) square
(©) angular

(©) angular

Explanation:

The tags should always be enclosed with a pair of angular brackets

In the case of Hyper text markup language (HTML) the brackets that should be used is angular brackets i.e. (< and >)

So as per the given situation, the option c is correct

And, the rest of the options are incorrect

Therefore the tags that should always enclosed with a angular pairs

Infrared

802.11-based

802.15-based

Explanation:

Infrared:

It's short distance wireless transmission - for example tv remote control using infrared waves.

802.11-based:

Mostly used for wifi and things like that...

802.15-based:

It's a bluetooth standart wireless data transmission method.