I'll give you a question, please answer with step-by-step reasoning process.
He was having a hard time expressing himself in a healthy way, the psychologist said he was mentally what?\nOptions:\n- slow\n- understood\n- suffering\n- embarrassment\n- fun

suffering
When a person is suffering, he cant express himself.

The psychologist said that he was having a hard time and was mentally suffering.

.

Thus, the answer is suffering