A student divides a difficulty into changeable and unchangeable parts, then works on the changeable part. Why is this effective?

Correct answer: It focuses energy on controllable actions

Separating controllable factors from uncontrollable ones prevents energy from being spent only on worry. The student can take practical steps, measure progress, and seek help where needed. Thus B is correct; the strategy does not guarantee success, erase every difficulty, or eliminate the usefulness of support.