61. Scientists' interest in three-parent children comes from the desire of eliminating ____.

1. a rare and life-threatening inherited disease
2. a huge number of rarely-occurring inherited diseases
3. the genetic influence from unhealthy parents
4. mutations in the nuclear DNA

62. Which of the following statements about mitochondrial transplantation is true?

1. It has been adopted as a medical procedure.
2. It has been proved scientifically feasible.
3. It is currently regarded as an illegal act.
4. It involves artificial DNA modification.

63. The application of mitochondrial transplantation might occur when ____.

1. medical technology becomes highly developed
2. it can be tested to lead to a healthy baby
3. it is proven that family resemblance will not be affected
4. genetic engineering is socially accepted

64. What is the author's attitude towards the public "uggh" factor?

1. Ironic.
2. Understanding.
3. Appreciative.
4. Ambivalent.

65. The last paragraph implies that mitochondrial transplantation ____.

1. is controversial but worth pursuing
2. is technically feasible but morally unacceptable
3. is a technique with little bad consequences
4. is a long-awaited answer to mitochondrial diseases

(Reference keys.)