Alice wants to sign and then send a confidential letter M to Bob. Which one of the following is sent by Alice to Bob. Let

Apk: Alice's public key
Apr: Alice's private key
Bpk: Bob's public key
Bpr: Bob's private key
E(M, K): Encryption the message M with the key K
D(M, K): Decryption the message M with the key
K H(M): Hash value of M

(Select all that apply.)

1. A->B: E(H(M, Apk))
2. A->B: E(H(M), Bpr)
3. A->B: E(E(M, Apk),Bpk)
4. A->B: E_Apk(E_Bpr(M))
5. A->B: ED(M, Apr), Bpk)
6. A->B: E(E(M, Apr), Bpk)
7. A->B: D(E(M, Apr), Bpk)
8. A->B: E(E(M, Apr), Bpr)
9. A->B: E(H(M),Bpk)