请选择CBA5O5N,{;t0z8v0T5j:[/m4R)S-QMy grandpa _______a flute player before.9p6^+D2O+V4O6_4j4C2a
A. is9p6^+D2O+V4O6_4j4C2a
B. was9p6^+D2O+V4O6_4j4C2a
C. were9p6^+D2O+V4O6_4j4C2a