The Bond Angles in CH₄, NH₃, and H₂O Are 109

The bond angles in CH₄, NH₃, and H₂O are 109.5°, 107°, and 104.5°, respectfully. Which of the statements best describes the variance in bond angles?

A) CH₄ has no lone pairs of electrons on the central atom so the optimal molecular shape would be tetrahedral with bond angles of 109.5°. In NH₃ and H₂O there are 1 and 2 lone pairs, respectfully, so more repulsion exists between the bonds and lone pairs, as a result, the bond angles are less than 109.5°.
B) NH₃ and H₂O have a trigonal pyramidal and bent molecular shape, respectfully, which is the reason why the bond angles are less than 109.5°.
C) CH₄ only has nonpolar bonds while NH₃ and H₂O have polar bonds which results in the difference in bond angels.