Read the given paragraph and answer the question:

Humans have 23 pairs of chromosomes. 22 pairs are exactly same in both males and females; these are the autosomes. A pair of X-chromosome are present in the female, whereas the presence of an X and Y chromosome are determinant of the male characteristic. A number of disorders in human beings have been found to be associated with the inheritance of changed or altered genes or chromosomes. Broadly, genetic disorder may be grouped into two categories disorders and Chromosomal disorders.

What is the probability of having a daughter to a couple expecting their first child?

50%

The correct answer is Option (3)- 50%

The probability of having a daughter to a couple expecting their first child is 50%. This is because the sex of the child is determined by the combination of genetic material from both parents, with each parent contributing one sex chromosome. In humans, females have two X chromosomes (XX) and males have one X and one Y chromosome (XY).

When the father's sperm containing either an X or a Y chromosome fertilizes the mother's egg (which contains an X chromosome), there are two possible outcomes: XX (female) or XY (male). Since each outcome is equally likely, the probability of having a daughter (XX) is the same as the probability of having a son (XY), which is 50%.

Therefore, the correct answer is option 3: 50%.