Answer:
The central idea is to show how the foods offered in American supermarkets are very convenient, but unhealthy and attractive.
Explanation:
According to the article, we can see that as we age and understand more about healthy foods, the foods offered by supermarkets become less interesting. That's because, as adults, we look for the ease and practicality of frozen, extremely processed foods, fast food, among others. These foods do not propose a safe diet and can be very harmful, however, when an individual opts for healthier foods, he finds it difficult to find them in supermarkets.
The sentence presented above is an example of a complex sentence based on its structure. A complex sentence contains an independent clause and a dependent one. In the given the independent clause is the man was already listening to his new iPod and the dependent clause is ready to go out for his daily jog around Central Park.
My educated guess would be that "in an old bus" is the object of the preposition.
