WASHINGTON, Dec 1 (Reuters) - The top executives of eight major cryptocurrency firms, including Coinbase Global Inc (COIN.O), will testify before the U.S. House Financial Services Committee on Dec. 8, the panel announced on Wednesday. The hearing marks the first time major players in the rapidly growing crypto markets will testify before lawmakers, as policymakers grapple with the implications of the new financial product and how to best regulate it. Some progressives have become increasingly skeptical of cryptocurrency and the risks they may pose, with Senator Elizabeth Warren, among others, calling for a regulatory crackdown on the volatile sector. Alesia Haas, the CFO of Coinbase Global, will be among witnesses at the hearing, which will focus on "the challenges and benefits of financial innovation," according to the committee announcement.Jeremy Allaire, the CEO of Circle, Sam Bankman-Fried, CEO of FTX Trading, Chad Cascarilla, CEO of Paxos, and Dennelle Dixon, CEO of the Stellar Development Foundation, will also be witnesses at the hearing. Also testifying will be Brian Brooks, the current CEO of Bitfury, who previously served as a top banking regulator under the Trump administration. As the acting Comptroller of the Currency, Brooks pushed forward several policies aimed at making it easier for banks to engage with cryptocurrency.