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Consider the following $ER$ model: 

If $‘n’$ entries in $E_1$ and $‘m’$ entries in $E_2$. How many entries in relationship set $(R)$?

  1. At least $n$
  2. At most $n$
  3. Exactly $n$
  4. At least $n$ and atmost $m$
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There are some Conventions that Arrow ( $\rightarrow$) Mark represents $One$ and Straight line ( $-$) represents $Many$, Hence here One to One Relationship.

And Single line represents Partial Participation and Double line represents Total Participation.. Hence here, $E1$ is having Total Participation in the Relationship $R$ and $E2$ is having Partial relationship in $R$.

Now, Because of Total Participation of $E1$, $R$ has to contain at least $n$ rows. But Because of One to One relationship, We can't have more than $n$ rows in $R$ (Try it and see)

Hence answer would be Option $C$ But with added condition that $m > n$
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