This only multiple choice.. provide explaination if necessary only. thank you.

1. Who is the mathematician responsible for 9. Suppose the Caesar cipher is used to encrypt inventing the machine that helped break the the message QUICK. Which of the following German enigma code? cipher text corresponds to this plain text? (a) Leonard Adleman (a) TIXFN b) Alan Turing (b) TXLEN c) Ronald Rivest (c) TXLNF (d) Richard Hamming (d) None of the above 2. Which of the following is FALSE? 10. Which of the following refers to the property (a) For any three integers a, b, and c, if that the receiver is guaranteed that the a=b( modn) and bec(mod n) , then message really came from the real sender? asc(modn). (a) Authenticity (b) For any integer b, beb(modn). (b) Confidentiality c) For any two integers a and b, whenever (c) Non-repudiation a=b( modn) , then bea( modn). (d) Integrity (d) None of the choices is correct. 3. Which of the following is a polyalphabetic cryptosystem? (a) Dancing men cipher (b) Pigpen cipher c) Vigenere cipher (d) Caesar cipher 4. Which of the following numbers satisfy the equivalence relation 3x=1(mod 14) ? (a) 5 (b) 3 (c) 4 d) None of the above 5. Suppose the RSA cryptosystem is used with public key (35.7) . What is the corresponding cipher text when the plain text "2" is sent? (a) 23 (b) 15 (c) 12 d) 8 6. Which of the following refers to the property the sender and receiver are guaranteed that no third party can make any changes in the message that exchange in the transmission process? (a) Authenticity (b) Non-repudiation c) Confidentiality (d) Integrity 7- Suppose the RSA system that is used for sending secret messages has private key (15,3) and the cipher text "3" is received. What was the plain text sent? (a) 12 (b) 7 (c) 9 (d) 5 8. Suppose the Vigenere cipher is used to create the cipher text DOYMTOD using the keyword ROSE. Which of the following is its corresponding plain text? (a) MAGICAL (b) REASONS c) LOGICAL (d) SEASONS