Amniocentesis

Correct answer: A. Analysing fetal cells in amniotic fluid to detect certain chromosomal abnormalities.

Explanation: Amniocentesis involves collecting a sample of amniotic fluid, which contains fetal cells. These cells can be examined for certain chromosomal or genetic abnormalities. Option B describes chorionic villus sampling, option C describes maternal-serum screening, and option D describes ultrasonography.

Correct answer: A. It can promote sex-selective abortion, including female foeticide, and contribute to an imbalanced sex ratio.

Explanation: Amniocentesis is an invasive prenatal diagnostic procedure that can help identify certain genetic or chromosomal conditions. Using it solely for sex determination may encourage sex-selective abortion, including female foeticide, and can worsen an imbalanced sex ratio. It does not change the foetus’s chromosomes or cause permanent infertility in the mother.

Correct answer: A. Detecting foetal chromosomal abnormalities.

Explanation: The governing concept is prenatal diagnosis. In amniocentesis, a small sample of amniotic fluid is examined because it contains foetal cells and biochemical substances. Laboratory analysis can reveal chromosomal abnormalities, such as an abnormal chromosome number, and some genetic conditions before birth. Thus option A is a legitimate medical use. Sex selection is an unethical and legally prohibited misuse, while contraception and milk secretion are unrelated.

Correct answer: B. It can promote sex-selective abortion, including female foeticide, and disturb the sex ratio.

Explanation: The governing concept is the ethical and social regulation of prenatal testing. Although amniocentesis can diagnose chromosomal or genetic abnormalities, revealing foetal sex for non-medical selection may encourage sex-selective abortion. This can intensify discrimination against female foetuses and produce an imbalanced sex ratio. Therefore option B gives the valid reason; the other choices describe functions unrelated to amniocentesis.