In 1890, William James Argued That "By Age 30, the Character

In 1890, William James argued that "by age 30, the character [personality] has set like plaster and will never soften again." Has psychological research supported his assertion?

A) Yes, but his conclusion applies only to Western cultures.
B) Generally yes, but he underestimated the age at which change is reduced.
C) No; recent evidence indicates that dramatic changes occur at all ages.
D) No, because it all depends upon whether the individual stays in the same environment.