Moles: A = 2 mol (5 atoms each = 10 mol atoms). B = 4 mol (3 atoms = 12 mol atoms). C = 6 mol (3 atoms = 18 mol atoms). D = 6 mol (2 atoms = 12 mol atoms). E = 5 mol (3 atoms = 15 mol atoms). Equal atoms: B and D both have 12 mol atoms. Adding: A has 10N, C has 18N. So B and D are equal. But option (1) says B, C, D — let's recount: B: 4 mol × 3 atoms = 12N. C: 6 mol × 3 atoms = 18N. D: 6 mol × 2 atoms = 12N. B and D equal. Option (1) = B, C, D — incorrect. Option (2) = B, D, E: E = 5×3=15N ≠ 12N. Answer: B and D only = option (1)... Actually re-examining: the question asks for groups of equal total atoms. B=12N, D=12N match. None of the options say 'B and D only'. Closest is option (1) B, C, D.