Which factor plays there biggest role in delaying the detection of childhood disease

The correct answer is lack of knowledge of disease.

If a child has a disease and because he/she lacks knowledge of the disease then the child may end up passing away.

It is good for a parent to take all the vaccination which are needed for growth.

Diseases like measles a parent should follow all the required vaccination for a better growth of the child.

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answer; all of the above;

because health skills are tools and strategies and also practical skills are also something you need to learn (like tools and strategies) and put it in reality.