Choose the letter A, B, C or D to answer these following

This is Alex. He is twenty years old. He is a weight-lifter. He is tall and strong. He spends 2 hours practicing weight-lifting every day. Weightlifting is a hard and dangerous sports to play. Sometimes, Alex hurts himself while doing the sport. But he never gives up. He wants to be a champion in the future. All the family members are proud of him. He will take part in a sport competition next week. Would you want to come along and watch the match?

How old is Alex?