Electronegativities of the elements be, mg, ca and sr follow a specific trend within their group. based on this trend, te atoms of which element will have the least attraction for an electron?

Sr

Explanation:

Electronegativity is the tendency of an element to draw electrons towards itself. The higher the electrongtaivity the greater is the tendency of the element is to draw the electrons towards itself and vice versa.  

Electronegativity decreases down a group in the periodic table. Down a group the atomic size of the element increases as new shells get added. When the atomic size increase the tendency of the element to draw the electron towards itself decreases.  

it's all four options.