There are 20 random box lunches at a conference for teachers. They are all the same except 10 of the lunches have peanut butter cookies, 5 have snicker doodle cookies, and the last 5 boxes have chocolate chip. Knowing this a math teacher realizes that he has a 25% chance of randomly picking a box with a chocolate chip cookie. What type of probability did the teacher use?
A) Empirical probability
B) Authentic probability
C) Subjective probability
D) Theoretical probability