(1) The wide availability of canned, frozen, and precooked foods has definitely improved people's lives by freeing up time that used to be spent preparing meals. (2) However, these convenience foods have also had some negative consequences. (3) One effect has been a rise in obesity. (4) Because plentiful convenience foods need little to no preparation time, many people have developed a tendency to eat too much and put on too much weight. (5) These foods also tend to contain unhealthy ingredients like preservatives and high amounts of salt. (6) Therefore, people who rely too heavily on them can find themselves with health problems such as heart disease. (7) Another negative result of convenience foods has been the death of family dinner time. (8) Now that people can grab prepackaged foods on the run, they just don't try as hard to sit down to a meal as a family. (9) Convenience foods have also contributed to Americans' rushed lifestyle overall. (10) Unfortunately, when it became easy to just microwave a burrito and keep going, sitting down and eating a relaxed meal seemed like a waste of precious time. Which sentence(s) have the cause & effect transitional words and expressions?

(3), (4), (6), & (7)
(2), (3), (4), (6), & (7)
(2), (4), (5), (6), & (7)​