Which of the following is a continuous variation, in human population?

Height is a continuous variation in the human population. Continuous variation refers to the variation in a trait that can take on a range of values, without distinct categories or breaks. Height is an example of a continuous variation in humans because it can vary from very short to very tall without distinct categories or breaks. In contrast, sex and Rh factor are examples of discrete or categorical variations because they fall into distinct categories of male/female and Rh positive/negative, respectively. Down's syndrome is also not a continuous variation because it is a genetic disorder caused by an extra chromosome, and it either occurs or does not occur in an individual. It does not fall into a range of values. In summary, height is an example of a continuous variation in humans, while sex, Rh factor, and Down's syndrome are not.