Read the Assertion and Reason below and choose the correct option. — Solid State Chemistry Question

💡 Solution & Explanation

In any close-packed structure of $N$ spheres, there are $2N$ tetrahedral voids. This occurs exactly because each sphere in a close-packed layer generates one tetrahedral void directly above it (formed with the upper layer) and one directly below it (formed with the lower layer), accounting for the 2:1 ratio. Therefore, correct answer is A.