Q1. What is the passage mainly about?

1. AHow to teach children to write
2. BA study about left-handed people's lives and its problem
3. CWhy right-handed people are stronger
4. DHow long people lived in 1991

左利きは早死にするという研究と、その問題点についての話なので B。

Q2. How many years earlier did the 1991 study say left-handed people died?

1. AAbout five years
2. BAbout seven years
3. CAbout nine years
4. DAbout eleven years

died about nine years earlier とあるので C。

Q3. In this passage, "shocked" means people were ...

1. Avery surprised
2. Bvery sleepy
3. Cvery happy
4. Dvery angry at the doctors

shocked は「衝撃を受けた・とても驚いた」。意外な研究結果に驚いた場面なので A。

Q1. How did the 1991 researchers collect their data?

1. ABy following living people for many years
2. BBy asking families of people who had died
3. CBy testing children in schools
4. DBy studying professional athletes only

They asked the families of about 1,000 people who had died とあるので B。死亡者の遺族への聞き取りだった。

Q2. Why were there fewer left-handers among older people?

1. ABecause left-handers had more accidents
2. BBecause older people forgot their handedness
3. CBecause many were forced to use their right hand as children
4. DBecause left-handedness is a new trait

many left-handed children were forced to switch to their right hand とあるので C。

Q3. What does the author suggest about the nine-year gap?

1. AIt was caused by how the data were collected.
2. BIt proves that left-handers are less healthy.
3. CIt was confirmed by the study of 3,800 Americans.
4. DIt only applies to people in California.

this gap was misleading とし、世代による左利きの割合の差で説明しているので A。後の追跡研究では差がなかった。

Q1. What is the main point of the passage?

1. ALeft-handers are more likely to have accidents.
2. BThe nine-year gap came from a flaw in how the data were compared.
3. CHandedness changes as people grow older.
4. DCricket players live longer than baseball players.

it is now widely regarded as a statistical artifact とし、世代による左利きの割合の差を説明しているので B。

Q2. According to the passage, why would left-handers in a sample of recent deaths appear to die younger?

1. ABecause they came disproportionately from younger generations
2. BBecause their relatives reported wrong ages
3. CBecause they had more serious illnesses
4. DBecause they were all from California

draw its left-handers disproportionately from younger cohorts, lowering their average age at death とあるので A。

Q3. Which research design does the author consider more reliable?

1. AAsking relatives about people who have died
2. BComparing the average age of the dead
3. CStudying only professional athletes
4. DRecording handedness in living people and following them

A better design is to record handedness in living people and follow them over time とあるので D。