The correct answer is 2) amable
Explanation:
In Spanish, adjectives (words that describe nouns) have to agree in number and gender with the nouns they describe. For example, if the noun is plural and feminine the adjective should be plural and feminine, this applies in case there is a different adjective for feminine and masculine nouns.
In the case "Juan", this is a masculine name and therefore represents one boy or man; therefore, the adjective should be singular and masculine. In this way, the correct adjective is "amable" because it is the only singular adjective, considering "amables", "altos" and "bajos" are all plural nouns; you can know this, because of they all end in -s and in Spanish language, most plural forms end in -s. Also, the word "amable" can be used to describe both feminine and masculine singular nouns; for example, Maria es amable or Juan es amable.
