you train a classifier with regularization value $($lambda$)$ on $10,000$ training points and obtain a training accuracy of $99\%.$ However, when you submit to Kaggle, your testing accuracy is only $67\%.$ Which of the following, done in isolation, has a good chance of improving your performance on Kaggle?

a$.$

Set your regularization value lambda to $0$

b$.$

Train on more data

c$.$

None of others

d$.$

Train on less data