Elements at the top right of the periodic table have high ionization energies because
A. their atomic radius is small
B. these elements are high in electronegativity
D C. layers of electron shells shield the protons' attractive force
D. they have fewer electron shells to shield the protons from the
electrons

B.) These elements are high in electronegativity

Explanation:

As you move right on the periodic table, the atoms get bigger. Atoms with more electrons have more shells. As the number of shells increase, the outermost electrons get further from the nucleus. As they get further from the nucleus, the protons have less of a hold on the electrons. This means they are more easily removed.

The elements on the top right of the table are smaller, and this means that the protons exert a greater force on their electrons. These factors make it difficult to remove their outermost electrons, increasing ionization energy.

they should be similar or the same