请问permissionless networks和permission networks的区别是什么？

问题如下：

The ownership and exchange of digital assets on permissionless networks are usually recorded on a:

选项：

A.

centralized ledger maintained by a central intermediary.

B.

decentralized ledger maintained by a central intermediary.

C.

decentralized ledger without any central intermediary.

解释：

The correct answer is C. The ownership and exchange of digital assets on permissionless networks are generally recorded on a distributed (i.e., decentralized) digital ledger using cryptography and enhanced algorithms without the use of any central intermediary.