Answer:
Ca
Step-by-step explanation:
As a general trend on the periodic table, the electronegativities of elements decrease down the group and increase across the periods. Since calcium is in group two , it is expected to have the lowest amount of electronegativity due to its specific location on the periodic table.
To show that this prediction is true, I will write the elecronegativity values of these atoms. Calcium has a value 1.0, Silver 1.93 , Iron 1.83 and chromium 1.66