The correct answer is option 1 which includes I, II and III. Let`s dissect each statement:

I. > It is less obese: This is generally considered true as breast milk has an optimal balance of nutrients that tailor to the infant`s needs, leading to a natural control of baby weight.

II. > It shows a greater capacity to resist diseases: This is also true due to immunological benefits of breastfeeding. Breast milk contains antibodies that help the infant build its immune system and fight off viruses and bacteria.

III. > It gets more vitamins and proteins: Breast milk indeed has a complex composition including vitamins and proteins. However, this isn`t necessarily more than formula milk, rather it contains the exact nutritional needs for the baby.

IV. > Its growth in height is abnormal: This isn`t necessarily true. Each baby grows at a different pace, regardless of being breastfed or bottle-fed. Studies have shown no significant difference in the overall height of children based on their infancy feeding method.

So, the correct answer is option 1: It includes all valid characteristics of a breast-fed baby, which are statements I, II and III.