The statement that both types of markets face equal counterparty credit risk is incorrect. Counterparty credit risk refers to the risk that a counterparty in a financial transaction will default on their contractual obligations. CCP markets are specifically designed to mitigate and reduce this risk. They do this through a variety of mechanisms, including the use of a central counterparty, which acts as the buyer to every seller and the seller to every buyer, thereby eliminating the risk of default by any single party. In contrast, OTC CCP markets, while they also use a central counterparty, are generally considered to be riskier. This is because OTC transactions are typically less standardized and more complex than those in CCP markets, making them more difficult to value and risk-manage. Furthermore, OTC markets are less transparent and have less stringent regulatory oversight than CCP markets, which can increase the risk of counterparty default. Therefore, it is not accurate to say that both types of markets face equal counterparty credit risk.

Choice A is incorrect. Both OTC CCP markets and CCP markets do require default fund contributions. This is a common mechanism used in both types of markets to manage the risk of a participant's default.

Choice B is incorrect. Posting of initial and variation margins are indeed common practices in both OTC CCP and CCP markets. These margins serve as collateral to cover potential future exposure that could arise from price changes.

Choice C is incorrect. While it's true that transactions are more standardized in CCP markets, they can also be standardized in OTC CCP markets depending on the specific product or contract being traded.