Option D
The constituent attributes of a Candidate key or simply the attributes of a candidate key are called the prime attributes.
Suppose ABC is one candidate key of a Relation R(ABCDEFGH). Then the attributes A, B and C all are prime attributes. Similarly if ABD is also another candidate key in the same relation R, then D is also the prime attribute. And conversely, an attribute that does not occur in ANY candidate key is called a non-prime attribute.
atomic attribute ,candidate attribute there is no such term exist in RDBMS so option A,B, are false