複選題

3. Which of the following statements about integers are incorrect?
(A) If gcd(a,b) = 1, then for any non-zero integer n, there is a pair of integers p and a such that pa + qb = n.
(B) The inverse of p module q exists only when ged(p,q) = 1 and q ＞ 1. (x = a (mod m.)
(C) The system has a unique solution modulo m， where m i are primes and=m₁ m₂...m_n.
(D) Ifp is prime, then for every integer a we have ≡1(mod p).
(E) In RSA, if Alice wants to send a secret message to Bob, Alice uses Bob's private key to encrypt the message and then send the ciphertext message to Bob. After Bob receives the ciphertext, Bob can use his public key to decrypt the ciphertext.