1. Assertion (A): In human beings, the females play a major role in determining the sex of the offspring. 2. Reason (R): Women have two- ‘X’ chromosomes.

1. Assertion (A): "In human beings, the females play a major role in determining the sex of the offspring." This statement is false. 2. Reason (R): "Women have two 'X' chromosomes." This statement is true (genotype XX). 3. Sex determination in humans depends on the sex chromosome carried by the sperm. Females produce eggs containing only the X chromosome. Males produce sperm carrying either an X or a Y chromosome. If an X-carrying sperm fertilizes the egg, the offspring is female (XX). If a Y-carrying sperm fertilizes the egg, the offspring is male (XY). Therefore, the male determines the sex of the offspring. 4. Since A is false and R is true, the correct option is (D).