Answer:
B) Symmetrical and nonpolar
Step-by-step explanation:
The formula is H-C≡C-H.
Each C atom has <em>two</em> electron regions, so VSEPR theory predicts a <em>linear molecular geometry</em> (see image below).
The molecule is symmetrical, because the green line divides the molecule into two halves that are mirror images of each other.
The C-H bonds are slightly polar, because C is more electronegative than H (µ ≈ 0.4 D).
The C atoms are partially negative (red), while the H atoms are partially positive (blue).
However, the two C-H bond dipoles point in <em>opposite directions</em>, so they cancel each other. The molecule has <em>no net dipole moment.</em>
Acetylene is nonpolar.
