Which of the following orders of atomic radii is correct? MCQ with Answer and Explanation

Which of the following orders of atomic radii is correct?
A. I > Br > F > Cl
B. Na > Mg > Al > Si
C. O > N > C > B
D. F > Cl > Br > I
Answer: Option B
Solution (By JKExamLibrary)
Across a period from left to right, atomic radius decreases due to increasing effective nuclear charge. Therefore, the correct order for period 3 elements is Na > Mg > Al > Si. Down a group, radius increases, so F < Cl < Br < I. Options A, C, and D have incorrect trends.

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