The correct answer is 'Noun'. Key Points - Here, in the given above sentence, the underlined part "bottomline" is used as a noun. - As per the general rule, a noun is a word that names something, such as a person, place, thing, or idea. - Example: - This is an area of outstanding natural beauty. - Rates of home ownership have remained relatively constant. - Here, in the given above examples, 'beauty and ownership ' can be used as a noun. - According to the explanation and example that are given above, 'Noun' is the correct part of speech for the given above sentence.