Windows offers $\_\_\_\_\_\_\_\_$for full disk encryption. It can protect the entire system volume as well as other volumes in one of three modes. $\_\_\_\_\_\_\_\_$ is the most common mode for booting a system that does not have TPM $($Trusted Platform Module$)$ support?a$.$EFS $($Encrypted File System$)$; User authentication modeb.BitLocker; Transparent modec.EFS; USB key moded.BitLocker; USB key mode