Concept:Vitamins are organic substances that we need in sufficient quantities to maintain good health.Our body, however, cannot synthesize them. Therefore, we need to consume natural sources such as fruits and vegetables. Vitamins are divided into two groups water-soluble vitamins (Vitamins of B group and Vitamin C) and fat-soluble vitamins (Vitamins A, D, E, and K).Explanation:Rickets is a condition in which children's bones soften and weaken as a result of a severe and long-term vitamin D deficiency.Vitamin D is needed for the absorption of calcium ions from the duodenum walls into the bloodstream and also maintains calcium levels in the body.A few foods, such as canned salmon with bones and egg yolks, naturally contain trace amounts of vitamin D. Vitamin D can also be obtained through fortified foods and sun exposure.Vitamin D is a key component in the formation of strong bones. Additional InformationVitaminDeficiency diseasesSymptomsVitamin CScurvyBleeding gums, wounds take a longer time to heal.Vitamin DRicketsBones become soft and bent.Vitamin ALoss of visionPoor vision, loss of vision in darkness (night), sometimes complete loss of vision.Vitamin BBeriberiWeak muscles and very little energy to work.