Metallic character decreases across a period

Steps:

• Metallic character trends left to right in a period: decreases due to higher nuclear charge pulling electrons closer.
• Locate elements: Gallium (Group 13, period 4) left of Germanium (Group 14, period 4).
• Compare: Ga more metallic (loses electrons easily) than Ge (more non-metallic).
• Check alternatives: B incorrect on ion charge; C misstates electron count; D wrong on naming reason.

Why A is correct:

• Metallic character decreases across a period as electronegativity increases, per periodic trends (gallium, group 13, more metallic than germanium, group 14).

Why the others are wrong:

• B: Group 15 elements form -3 ions (e.g., nitride), not -5, due to gaining 3 valence electrons.
• C: Same-group elements share valence electrons (outer shell), not total electrons.
• D: Transition elements named for d-block position and variable oxidation states, not melting behavior.

Final answer: A