Answer:
Option D. 1
Explanation:
A bag contains a mixture of almonds, walnuts and cashews in an equal quantity of each nut.
If a nut is chosen randomly out of the bag,
Each have the same probability, that the nut is either an almond, a walnut or a cashew.
P (Almond) =

P (Walnut) =

P (Cashew) =

P (almond or walnut or Cashew) = P(almond) + P(walnut) + P(cashew)
P =
=

P = 1
The probability that a nut is either an almond, a walnut or a cashew is 1.