Uranium isotopes have 92 protons but different total nucleons.

Steps:

• Uranium's atomic number is 92, so all isotopes have Z = 92 protons.
• Original description gives A = 235, N = 146, so Z = 89, inconsistent; likely meant A = 238 for standard U-238 (Z = 238 - 146 = 92).
• Another isotope must have Z = 92 but different A (thus different N = A - 92).
• Check choices: subtract N from A to find Z, confirm same Z=92 and different A from 238.

Why A is correct:

• A=235, N=143 gives Z=92 (standard U-235), different A from original U-238.

Why the others are wrong:

• B and C: A=238, N=146 gives Z=92, but same as original (not another isotope).
• D: A=241, N=146 gives Z=95 (not uranium).

Final answer: A