Q46

In the RSA public key cryptosystem, the private and public keys are $(e, n)$ and $(d, n)$ respectively, where $n=p \times q$ and $p$ and $q$ are large primes. Besides, $n$ is public and $p$ and $q$ are private. Let $M$ be an integer such that $0<M<n$ and $\phi(n) = (p-1)(q-1)$. Now consider the following equations. Which of the above equations correctly represents RSA cryptosystem? I and II I and III II and IV III and IV