DBM301_-_RE_-_SU_2023_593.webp

(Choose 1 answer)
Consider the database containing the transaction T1: (a1, a2, a3), T2: {a2, a3, a4}, T3: (a1,a3, a4). Let mini-support (minsup) = 2. Which of the following frequent patterns is NOT closed?
A. {a2}
B. (a1, a3}
C. (a3}
D. (a3, a4}