Usage of definite/indefinite article

[Snappy]

Which underlined one is acceptable in the following case?

A: How long do people have to study to become lawyers in Japan?
B: It depends on 1. people 2. the people 3. people to people 4. a person 4. the person 5. person to person.

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We must classify these materials according to 1. grade. 2. grades 3. the grade.

Thank you in advance.

[TheParser]

Which underlined one is acceptable in the following case?

A: How long do people have to study to become lawyers in Japan?
B: It depends on 1. people 2. the people 3. people to people 4. a person 4. the person 5. person to person.

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We must classify these materials according to 1. grade. 2. grades 3. the grade.

Thank you in advance.

***NOT A TEACHER***Well, I THINK that the following answers are out of the question: people/ people to people/ a person/person to person. I think "the people" might be grammatically correct but certainly not idiomatic. I choose to interpret the question as: How long must one/a person study to become a lawyer in Japan? Well, it all depends on the person.