A

To find the number of α-particles and β-particles emitted when uranium decays to lead, we analyze the decay process step by step. The total change in mass number and atomic number during the decay gives insight into the emissions.

• The initial nucleus is Uranium-238 (U-238) with a mass number of 238 and atomic number 92.
• The final nucleus is Lead-206 (Pb-206) with a mass number of 206 and atomic number 82.
• In each α-decay, the mass number decreases by 4 and the atomic number decreases by 2.
• In each β-decay, the mass number stays the same, but the atomic number increases by 1.

We can set up the equation based on the number of α and β emissions:
Mass number: 238 - 4x = 206
Atomic number: 92 - 2x + y = 82
Solving these equations:
From mass number: 4x = 32 => x = 8 (number of α emissions).
From atomic number: 92 - 2(8) + y = 82 => y = 82 - 76 => y = 6 (number of β emissions).
Therefore, the number of α particles emitted is 8, and the number of β particles emitted is 6.