Solution:The pattern followed here is :(a, b, c) → {(a + b) × (a - b)} = c
(15, 13, 56) → {(15 + 13) × (15 - 13)} ⇒ 28 × 2 = 56
(17, 11, 168) → {(17 + 11) × (17 - 11)} ⇒ 28 × 6 = 168
Similarly,
(20, 14, 204) → {(20 + 14) × (20 - 14)} ⇒ 34 × 6 = 204
Hence, "(20, 14, 204)" is the correct answer.