Element P, Q, R and S have 6, 11,15 and 16 electrons respectively, therefore

Explanation

This question is testing your understanding of chemical bonding and electron configurations of different elements. Element P has 6 electrons, Q has 11, R has 15 and S has 16 electrons.

Ionic bonding occurs when an atom loses or gains electrons to achieve a full outer shell. Covalent bonding occurs when atoms share electrons to complete their outer shells. Electrovalent or polar covalent bonding occurs when there is a difference in the electronegativity of the atoms that are bonding.

Since element Q has 11 electrons, it needs one more electron to complete its outer shell and become stable. Element S has 16 electrons, which means it needs to lose two electrons to complete its outer shell. Therefore, element Q will form an electrovalent bond with element S, where Q will gain one electron and S will lose two electrons to form a stable compound.

Option D is the correct answer. Option A cannot be correct because elements P and R have a large difference in the number of electrons, making it unlikely for them to form an ionic bond. Option B is incorrect because both elements R and S are non-metals, making it unlikely for them to form an electrovalent bond. Option C is incorrect because both elements Q and S are non-metals, making it unlikely for them to form a covalent bond.

To learn more about chemical bonding and electron configurations, please read the relevant sections of your recommended textbooks.