On the problem of Database Paradigm

Hello, great gods, today I saw a topic about database paradigm, the b option of this question is B, but the relational mode of this question should not reach 2NF, right?

according to definition:
for example, if the relational schema R 1NF (that is, R conforms to the first normal form) and every non-principal attribute is completely dependent on the master code of R, then R 2NF (that is, R conforms to the second normal form).

in this topic, for example, the subject instructor, where the lecturer does not rely on the master code. (student, subject) score, in which the score is only a part of the main code, so it should not belong to 2NF ah?

also ask the great gods to analyze it. Maybe the answer is wrong, or my understanding of 2NF is wrong. Thank you!

Mysql

Sep.16,2021

the second paradigm is that attributes other than primary keys are completely dependent on all primary keys
, that is, all primary keys together can determine the only other attributes
what you call subject instructor. Among them, the lecturer does not rely on the master code , but the lecturer still depends on time and of student. Several other attributes are also similar to
time and student can determine the unique values of all other attributes, and there is no such thing as relying solely on a student or time . It satisfies second normal form
, but there is indirect dependency, so it does not satisfy third normal form

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