4y + 3 ≤ y + 6
4y + 3 - 3 ≤ y + 6 - 3
4y ≤ y + 3
4y - y ≤ y - y + 3
3y ≤ 3
3y/3 ≤ 3/3
y ≤ 1
So any value of y less than or equal to 1 (so 1 is included in the solution set) satisfies the inequality. C is the correct answer.
