[单选题]
A 4.0-kg object is attached to a spring of xdb78fy 0b1aa3xplp+ spring )90wvzlawn:vs sp d)/ constant 10 N/m. The object is dids9ap sv/nvw0 ):zwl)splaced by 5.1 cm from the equilibrium position and let go. What is the frequency of vibration?
A. $0.25 \; Hz$
B. $0.50 \; Hz$
C. $1.0 \; Hz$
D. $2.0 \; Hz$