Answer : The correct option is, (A) a 10 kg ball thrown with a 50 Newton force
Explanation :
Formula used :

where,
F = force
m = mass
a = acceleration
Calculate the acceleration for option (A) :

Calculate the acceleration for option (B) :

Calculate the acceleration for option (C) :

Calculate the acceleration for option (D) :

From this we conclude that option (A) have the greatest acceleration.
Hence, the correct option is, (A)