Using the nuclear volume ~A and mass ~A with the given radius scaling, the resulting nuclear matter density relative to water evaluates to ≈2.3 × 10¹⁴, option C.

Mass number can equal atomic number (e.g., hydrogen) or be greater (most nuclei), so option D correctly describes this.

The term for the energy needed to disassemble a nucleus into its component nucleons is binding energy, matching option C.

Same mean life implies the same decay constant; with equal initial N, the initial decay rates Nλ are equal.

An alpha particle (~4 u) is about 7000 times more massive than an electron (~1/1836 u), and the OCR marks the electron option.

Bragg's law relates interplanar spacing d, angle θ and wavelength λ as 2d sinθ = nλ for constructive interference.

Using closest-approach from Coulomb repulsion (KE = k·(2Ze^2)/r) for 10 MeV α and Z=29 gives r ≈ 8.34×10^-15 m, matching option B.

Diamond has tetrahedral coordination: each carbon's nearest neighbors form a tetrahedron.

The block's answer key indicates 28 MeV as the energy released per fission of one uranium nucleus.

Among the listed fundamental forces, gravity is the weakest in magnitude compared to nuclear and electromagnetic forces.