What is the symbol for sodium sulfur in cesium in order of increasing atomic radii

The symbols are correct but the order is incorrect.
The correct order is S, Na, Cs.
Na and S lie in the same 3rd period of the periodic table and atomic radius decreases across the period.
Na and Cs lie in the same group and Cs is in 6th period and atomic radius increases down the group. So the above order is the correct order of elements in increasing order of atomic radii.

The answer is letter c