Which of the following is not one of the tasks performed by the miners within the Bitcoin’s network?

I.   Providing potential users of bitcoin with a wallet.  

II.   Verifying a bitcoin transaction took place between two parties and then distribute it to the entire network.

III.   Every bitcoin miner usually keeps a copy of the entire blockchain on his/her computer.

IV.   Scrutinizing various updates, like the authentication of new blocks, which are provided by the network of bitcoin miners at large.