here, it says Which of the following represents a chal Kogen with the greatest effective nuclear charge? Remember, a chal Kogen is an element that is in Group six A. So what we have to do here is figure out which element or elements are groups. Six A. If we take a look, we have chlorine, lithium, sulfur, delirium and neon. The only elements from this list that are in Group Six A are sulfur and delirium. Remember, the general trend is as we head towards the top right corner of the periodic table that are effective, nuclear charge is going to increase. So here we have sulfur, which is in group six a below it a few few spaces below it is delirium. So based on this trend, as we move up, a group effective nuclear charge should increase. That would mean that sulfur would be the chalk agent with the greatest effective nuclear charge from the options provided