Electron count in neutral atoms

Steps:

• Identify atomic numbers: Cl (17), Ar (18), Kr (36).
• Neutral atoms have electrons equal to atomic number.
• Compare pairs: A ([Cl], [Cl]) both 17 electrons.
• Check others: B and C ([Ar], [Kr]) 18 vs. 36 electrons; D incomplete.

Why A is correct:

• Both [Cl] are neutral chlorine atoms with 17 protons and 17 electrons, per atomic structure definition.

Why the others are wrong:

• B: [Ar] (18 electrons) and [Kr] (36 electrons) differ in electron count.
• C: Identical to B, so same mismatch.
• D: No pair specified, lacks information for comparison.

Final answer: A