β+ Decay Alters Proton to Neutron, Changing Quark Composition

Steps:

• β+ decay converts one proton to one neutron, yielding 5 protons and 6 neutrons in the product nucleus (boron-11).
• Each proton has 2 up quarks and 1 down quark; each neutron has 1 up quark and 2 down quarks.
• Protons contribute: 5 × (2 up + 1 down) = 10 up + 5 down.
• Neutrons contribute: 6 × (1 up + 2 down) = 6 up + 12 down.
• Total quarks: 16 up + 17 down.

Why B is correct:

• Matches exact quark tally from standard proton/neutron compositions after β+ decay.

Why the others are wrong:

• A: Underestimates up quarks, overestimates down (ignores decay effect).
• C: Reverses up/down counts (confuses proton/neutron quark ratios).
• D: Overestimates up quarks, underestimates down (reverses initial carbon-11 counts).

Final answer: B