Ontario Grade 9 Science Class Practice Exam 2026 – Your Complete Guide to Exam Success!

A constellation is a group of stars that forms a pattern in the sky. Option A, a single star, is incorrect because a single star cannot form a pattern in the sky. Option B, a planet in our solar system, is also incorrect because planets do not form patterns in the sky that are recognized as constellations. Option C, a group of planets, is incorrect for the same reason as option B. Therefore, the only correct option is option D, a group of stars that forms a pattern in the sky.