correct
頙 centers on correctness or being right. The given meaning 'correct' is the sole gloss, so the kanji likely expresses the idea of something being accurate, proper, or set right.
頙 is a rare character. It combines 正 (correct, right) with 頁 (head, page), possibly suggesting a head that is upright or correct. The exact historical development is uncertain.
The left side 正 means correct, and the right side 頁 looks like a head with a large eye. Imagine a head held high and straight, showing that everything is correct and proper.
For サク, picture a sack of correct answers: sack -> サク, and every answer inside is right.