Analyze One of your classmates draws an electron dot diagram for a helium atom
with two dots. He tells you that these
dots mean each helium atom has two
unpaired electrons and can gain, lose,
or share electrons to have four pairs of
valence electrons and become stable. What
is wrong with your classmate's argument?

no entiendo del todo el inglés

answer: option (b) is the correct answer.

explanation:

a covalent bond is formed by sharing of electrons. whereas polarity arises due to difference in electronegativity of two atoms.

therefore, more is the electronegativity of an atom which combines with the titanium, more readily it will induce a partial positive and negative charge.

thus, out of the given options fluorine is most electronegative and has an incomplete octet. therefore, it will readily combine with titanium to share the electrons and complete its octet.  

it is b that is the answer.