Part 3: Reading Comprehension IIIDirections: There are four passages in this part. Each passage is followed by some questions. For each of them there are four choices marked A, B, C and D. You should decide on the best choice (2 mark each).CGrowing a human being can be huge. The body goes through a massive physical transformation, and the changes don’t end there. A research team led by neuroscientist Elseline Hoekzema performed brain scans on first-time mothers before and after pregnancy and found significant gray matter changes in brain regions related to social cognition and theory of mind.One major change during pregnancy is an enormous increase in sex steroid hormones such as progesterone (孕酮) and estrogen (雌激素). The only other occurrence of such change happens during puberty (adolescence), when these hormones cause dramatic structural and organizational changes in the brains. Teenagers lose gray matter as the unnecessary brain connections are pruned, and their brains are sculpted into their adult form. Very little research has focused on anatomical (解剖的) brain changes during pregnancy, however. Hoekzema and her colleagues performed brain scans on first-time mothers soon after their pregnancy and two years after their childbirth. Men and women who were not trying to have a child as well as first-time fathers were also scanned. The researchers also performed brain scans on the new mothers while they looked at photos of their infants. The scientists, using a standard scale to rate the attachment between mother and infant, found that the new mothers experienced gray matter reductions that lasted for at least two years after birth. Such loss was not seen in new fathers or nonparents. However, it is not necessarily a bad thing. It occurred in brain regions involved in social cognition, which had the strongest response when mothers looked at photos of their infants. These brain changes could also be used to predict how mothers scored on the attachment scale. In fact, these researchers were able to use computers to identify who were new mothers based only on their patterns of gray matter loss.It is unclear why this is happening, but Hoekzema thinks it may be because their brains are becoming more specialized to help them adapt to motherhood and respond to the needs of their babies. Although the present study focuses primarily on documenting brain changes during pregnancy, the study also offers some preliminary evidence to support this idea. Hoekzema expects follow-up work to tackle more applied questions such as how brain changes relate to postpartum depression (产后抑郁). Mel Rutherford, an evolutionary psychologist, is enthusiastic about the study. “The most exciting thing is that they have the longest-term evidence that we’ve seen of changes in the brain after pregnancy.” Rutherford has done a similar research on cognitive changes during pregnancy, only from an evolutionary perspective. “As a parent, you have different priorities and different tasks, and so your brain changes,” he explains. 79. Which of the changes do women go through during pregnancy, according to the passage?

A. Weight gains.
B. Attachment decreases.
C. Estrogen increases.
Depression reduction.