Which of the following karyotype is expected to be associated with abnormal phenotype [Note: 't' is translocation, and 'del' is deletion]:

Correct Answer: A

Rationale: 46, XX, del5p (A) causes Cri du Chat syndrome. Rationale: 5p deletion leads to severe phenotypes (cat-like cry, microcephaly). Balanced translocations (B, D) are normal; 22p deletion (C) is often benign (heterochromatic).

Correct Answer: B

Rationale: Eye lens cells (epithelial) are diploid (2n=46), like most somatic cells. 'B' is correct. Rationale: Haploid (n=23) is for gametes, triploid (3n) and tetraploid (4n) are abnormal and rare in humans. Lens cells divide mitotically, maintaining diploidy.

Correct Answer: A

Rationale: Beta satellite DNA is on the p-arm of acrocentric chromosomes (e.g., 13, 14, 15, 21, 22). 'A' is correct. Rationale: These repetitive sequences are near nucleolar organizer regions (NORs) on short arms, distinct from centromeric alpha satellites.

Correct Answer: D

Rationale: 69, YYY (D) cannot occur in triploidy. Rationale: Triploidy (3n=69) results from dispermy or diploid gametes (e.g., XXY, XXX), but YYY requires three Y-bearing sperms, biologically implausible in humans.

Correct Answer: A

Rationale: 1 maternal, 1 paternal set (A) is normal. Rationale: Diploidy (2n=46) requires 23 chromosomes from egg and sperm; deviations (B-D) cause moles or lethality.