Final answer:
The polarization power for cation is determined by effective nuclear charge. The s block is the block in which this phenomenon occurs.
Step-by-step explanation:
The block in which polarization power for cation is determined by effective nuclear charge is the s block.
The effective nuclear charge of an atom increases as the number of protons in an atom increases. This phenomenon can explain the decrease in atomic radii we see as we go across the periodic table. The effective nuclear charge experienced by the outermost electrons in cesium is much less than expected, which is why cesium is much larger than lithium.
In summary, the effective nuclear charge determines the polarization power for cation and changes relatively little for electrons in the outermost shell due to the shielding effect of the filled inner shells.