A Thumbtack Is Tossed Repeatedly and Observed to See If

A thumbtack is tossed repeatedly and observed to see if the point lands resting on the floor or sticking up in the air. The goal is to estimate the probability that a thumbtack would land with the point up. That probability is an example of

A) a relative frequency probability based on long-run observation.
B) a relative frequency probability based on physical assumptions.
C) a personal probability.
D) a probability based on measuring a representative sample and observing relative frequencies that fall into various categories.