Demonstrative adjective 'those' needs to be replaced with possessive determiner 'their' to imply belongingness with the parents, teachers and elders.
The correct sentence is: Everyone should respect their parents, teachers, and elders.
Hence, option (b) is the answer.
Note:
Demonstrative Adjectives: Demonstrative adjectives include "this", "that", "these" and "those". These modify or describe a noun and come before a noun while 'demonstrative pronouns' replace a noun. Example: "I like that T-shirt of yours".
Possessive Determiners/Adjectives: Words like 'my', 'our', 'your', 'his', 'her', 'its', and 'their' are known as possessive adjectives (or possessive determiners). They come before nouns and indicate ownership of the noun. Example: "The teacher asked the students to open their drawing books."
Study Notes
Category
