All of the following are true EXCEPT thatA．attention－boosting training can improve focus a

All of the following are true EXCEPT that

A．attention-boosting training can improve focus and concentration at once.

B．financial pressure attracts more Americans to try their luck in gambling.

C．kindergarten is the best place to know about people"s impulsivity.

D．parents often unconsciously encourage kids to gamble.

请帮忙给出正确答案和分析，谢谢！