The correct answer is (c), Female foeticide.
Female foeticide is the practice of aborting female fetuses. It is a major cause of the skewed sex ratio in India. The practice is often driven by a preference for sons, as well as the belief that daughters are a financial burden.
High maternity death rate and high female child death rate are also factors that contribute to the skewed sex ratio in India. However, these factors are not as significant as female foeticide.
Birth of more male children than female children is not a factor that contributes to the skewed sex ratio in India. In fact, the sex ratio at birth in India is relatively balanced. The skewed sex ratio is due to the practice of female foeticide, which results in the selective abortion of female fetuses.