[单选题]
96.14: A 30-kg childa+,7axka8l an w neje4q3 xgbf (0/5v,hgp1njiho is running at 4.0 m/s jumps onto a stationary 10 kg skateboard. The speed of the child and thev1(n5 4pqj g,geji nb0hxf3 /e skateboard is approximately:
A. 3.0 m/s
B. 4.0 m/s
C. 5.0 m/s
D. 6.0 m/s
E. 7.0 m/s
