the main part of the microscope that is used to see and denlarge specimens what do you call this part?

I believe you are asking about the objective lens or eyepiece.

Explanation:

Objective lenses are used to magnify objects enough for you to see them in great detail

Eyepiece/Ocular is what you look through at the top of the microscope.

A tube connects the eyepiece lens to objective lenses, which enhance the magnification power of the eyepiece lens. Both the eyepiece and the objective lens contribute to the magnification of the object.

The eyepiece lens usually magnifies 10x, and a typical objective lens magnifies 40x.

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.