Which of the following statements are true with reference to the sex-determination in honeybees ?
A. An offspring formed from the union of a sperm and an egg, develops as a female (queen or worker).
B. An unfertilized egg develops as a male by parthenogenesis.
C. A male has half the number of chromosomes than that of a female.
D. Males produce sperms by meiosis.
E. Honeybees have a haplodiploid sex-determination system.
Choose the correct answer from the options given below :

(A) A, B, C and E only
In honeybees, sex determination is based on the haplodiploid system.
Statement A is correct. Fertilized eggs (diploid) develop into females, which can be either queens or workers depending on their nutrition.
Statement B is correct. Unfertilized eggs develop into males (drones) through parthenogenesis.
Statement C is correct. Males are haploid \((n=16)\) and females are diploid \((2 n=32)\), so males have half the number of chromosomes compared to females.
Statement D is incorrect. Since males are already haploid, they produce sperms by mitosis, not meiosis.
Statement E is correct. This entire mechanism is known as the haplodiploid sex-determination system.
Therefore, statements A, B, C, and E are correct.