Which of the statements below are correct

In cryptography an initialization vector $($IV$)$ does not always have to be random and can be a nonce $($i$.$e$.$ a number used only once, fulfing the non$-$repeating property$).$

The output feedback $($OFB$)$ mode of operation of the block cipher can be used as a keystream generator.

In the RSA cipher the public key has one part, while the private key has two parts used in modular algebra computations.

Cryptographically secure pseudo random numbers generators are nondeterministic.