Complete the following alphabetical sequence.

A, AC, DAD, FEE, JACK, _____________

Given: ​A, AC, DAD, FEE, JACK, _____________

Logic: Square root of (Sum of place values) = Position in sequence

A → 1 → √1 = 1 
AC → (1 + 3) = 4 → √4 = 2 
DAD → (4 + 1 + 4) = 9 → √9 = 3 
FEE → (6 + 5 + 5) = 16 → √16 = 4 
JACK → (10 + 1 + 3 + 11) = 25 → √25 = 5 
Checking Options:
(a) RIDE → (18) + (9) + (4) + (5) = 36 → √36 = 6 (Correct Answer)
(b) ARRIVAL → (1) + (18) + (18) + (9) + (22) + (1) + (12) = 81 → √81 = 9(Incorrect)
(c) SMELL → (19) + (13) + (5) + (12) + (12) = 61 →√61 ≠ 6 (Incorrect)
(d) FATHER → (6) + (1) + (20) + (8) + (5) + (18) = 58 → √58 ≠ 6  (Incorrect)

Therefore, the next word is RIDE.
Thus, the correct option is (a) RIDE.
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