Molecular geometries and bond types in VSEPR theory Steps:

• Recall VSEPR shapes: AX3E is trigonal pyramidal, AX4 is tetrahedral.
• Match to molecules: NH3 is pyramidal (3 σ bonds, 1 lone pair), CH4 is tetrahedral (4 σ bonds).
• Identify bond overlaps: σ from end-to-end, π from side-to-side; α may denote angle or hybrid.
• Compare rows: correct row pairs pyramidal with tetrahedral and appropriate overlaps (α π for hybrid-pi in context).

Why A is correct:

• Aligns with VSEPR definitions: pyramidal (molecular for NH3) pairs with regular tetrahedral (electron geometry), α π reflects hybrid (sp3) and pi (if extended to unsaturated analogs).

Why the others are wrong:

• B: Incorrectly swaps shapes and duplicates σ, ignoring pi in bonding variety.
• C: Retains shape pair but mismatches bonds; σ π confuses single-bond dominance.
• D: Shape pair correct but σ α mislabels; α not standard for bond type.

Not enough information for full context, but A fits standard pairings.

Final answer: A