Q1. What is the main message of the passage?

1. ACold rice is dangerous to eat.
2. BCold rice has a little more resistant starch, but it is not a magic food.
3. CHot rice has no starch.
4. DEveryone should eat only cold rice.

レジスタントスターチは少し増えるが量は少なく、研究結果も割れているので魔法の食べ物ではない、という内容なので B。

Q2. What happens to some starch when cooked rice gets cold?

1. AIt turns into sugar.
2. BIt disappears.
3. CIt becomes harder to digest.
4. DIt becomes sweeter.

This starch is harder to digest. とあるので C。

Q3. In this passage, "digest" means ...

1. Ato break down food in the body
2. Bto cook food in a pot
3. Cto keep food cold
4. Dto buy food at a store

digest は「消化する」、体の中で食べ物を分解することなので A。

Q1. In the 2015 study, what kind of rice was compared with freshly cooked rice?

1. ARice cooked with oil
2. BBrown rice
3. CRice kept at room temperature for three days
4. DRice chilled for 24 hours and then reheated

rice that was chilled for 24 hours and then reheated と比べているので D。

Q2. What did the 2013 study find?

1. ANo clear difference in blood sugar
2. BA much larger rise in blood sugar
3. CThat rice contains no starch
4. DThat cold rice causes weight gain

a 2013 study with 21 adults found no clear difference とあるので A。

Q3. What is the writer's attitude toward the claim that cold rice is healthier?

1. AThe writer completely agrees with it.
2. BThe writer thinks it is dangerous to eat rice.
3. CThe writer thinks it is partly true but the evidence is limited.
4. DThe writer has no opinion about it.

2015年の研究では血糖値の上昇が小さくなったが、2013年の研究では found no clear difference で、どちらも small studies、増える量も100gあたり1gほどと述べているので C。

Q1. What is the main point of the passage?

1. ACold rice is the best way to control blood sugar.
2. BCooling rice does increase resistant starch, but evidence of a blood sugar benefit is mixed.
3. CRice should never be reheated.
4. DResistant starch is harmful to the large intestine.

化学的には冷やすと増えるのは確か（The chemistry behind it is sound）だが、血糖値への効果は研究で割れている、という内容なので B。

Q2. According to the 2015 study, how much resistant starch did the chilled and reheated rice contain?

1. A0.64 grams per 100 grams
2. B50 grams per 100 grams
3. C2.55 grams per 100 grams
4. D1.65 grams per 100 grams

to 1.65 grams in rice chilled at 4°C for 24 hours and reheated とあるので D。0.64 g は炊きたて。

Q3. What does the writer suggest in the final sentence?

1. AHow much rice you eat and what you eat with it are likely more important than its temperature.
2. BPeople with diabetes should stop eating rice.
3. CRice should always be eaten cold.
4. DThe temperature of rice is the most important factor.

portion size and the rest of the meal probably matter far more とあり、温度より量や組み合わせが重要という主張なので A。