theory of growth and development

If a child's development is damaged by subjecting embryo to harmful radiation rays then it is considered as which influencing factor of growth and development?

Which of the followlng statements is not correct about growth and development?

The best method to study growth and development of the child is:

Assertion.Plant growth regulators are very important for plant growth and development Reason. Auxins do not induce flowering in gymnosperms.