Answer:
​Let the child participate in meal planning and grocery shopping
Explanation:
The child is very picky eater as mentioned in the question. He only eats what he likes and that results in monotonous food intake and can be dangerous.
His mother should encourage the child to participate in the meal planing process. Engage him by introducing various new things and educating about taste and benefits. She can also take him to grocery market where he may be fascinate by seeing other options also.