[单选题]
A proton strikes an oxygen-18 nucleus pr-ui;ff h 5h1(rpy7 cgjog7h pep deo 5a3+/oj/uagp*j* ducing fluorine-18 and another particle. What other particle is produced by the ag*jepp/ u og5/ jao7p3h+*dis nuclear reaction?
A. a neutron
B. an $\alpha$ particle
C. an $b-$ particle
D. an $b+$ particle
