Concept:Find the word that is most nearly opposite in meaning to the underlined word and that fits the gap correctly.Explanation:The underlined word "insignificant" means unimportant or too small to matter.Its opposite should mean important, noticeable, or worthy of attention.The word "remarkable" means worthy of notice or attention.So "remarkable" is the most nearly opposite in meaning to "insignificant" and correctly fills the gap.Answer:C. remarkable