Which of the following statements is true regarding steganography and cryptography?

Cryptography replaces bits of unused data from various media files with other bits that, when assembled, reveal a hidden message.

In cryptography, only one key is used to hide and extract data.

In steganography, the same key or two different keys for encryption and decryption can be used.

Steganography is used to hide information when encryption is not a safe option.