Consider the following ERD:

CENTRAL SCHOOL LIBRARY ERD

Time left $0$:$30$:$30$

IsWrittenBy

AUTHOR

Author$\_$Sequence

Author$\_$Sequence values reflect $1$ as first author, $2$ as second,

AuthoriD

AuthorName

etc.

In converting the ERD to its equivalent relations schema, how many tables do we end up with?

a$.5$

b$.2$

C$.3$

$?$

d$.4$