Set \(X = \{a, b, c, d, 9\},\) where \(a, b, c, d\) and \(9\) are five distinct positive integers. If \(9\) is the only odd integer in the set, what is the average (arithmetic mean) of set \(X?\)

(1) The standard deviation of set \(X\) is \(2.\)
(2) The range of \(\{a, b, c\}\) is \(4\) and the average (arithmetic mean) of \(\{a, b, c\}\) is \(10.\)

Answer: A

Source: GMAT Club Tests