What part of speech is the highlighted word in each sentence?

Choose the correct option.

I think this film is boring. [Noun|Verb|Adjective|Adverb]

Jill has got two brothers and a sister. [Noun|Verb|Adjective|Adverb]

My sister's favourite food is pizza. [Noun|Verb|Adjective|Adverb]

Mark rarely watches movies on the weekends. [Noun|Verb|Adjective|Adverb]