**Core Concept**
The World Health Organization (WHO) provides guidelines for optimal feeding practices for infants, emphasizing the benefits of exclusive breastfeeding for the first six months. Exclusive breastfeeding means that the infant receives only breast milk, without any additional foods or liquids, to support optimal growth and development.

**Why the Correct Answer is Right**
The WHO recommends exclusive breastfeeding for the first six months to promote optimal growth and development, improve cognitive development, and reduce the risk of infections and diseases. This recommendation is based on the understanding that breast milk provides the ideal mix of proteins, fats, carbohydrates, vitamins, and minerals for infants. Additionally, breastfeeding has been shown to have numerous benefits for the mother, including reduced risk of postpartum hemorrhage, breast cancer, and ovarian cancer.

**Why Each Wrong Option is Incorrect**
**Option B:** Exclusive breastfeeding for four months is not sufficient to meet the nutritional needs of infants beyond this age.
**Option C:** Eight months is too long for exclusive breastfeeding, as infants require additional nutrients and solid foods beyond this age.
**Option D:** Ten months is excessively long for exclusive breastfeeding, as it can lead to nutrient deficiencies and other health problems.

**Clinical Pearl / High-Yield Fact**
Breastfeeding should be initiated within the first hour of life, and the mother should be encouraged to breastfeed exclusively for at least six months, with continued breastfeeding up to two years or beyond.

**✓ Correct Answer: A. 6 months**