Match the following types of conditioning with their correct explanation:
| A. Trace | I. A tone is played and continues to sound. After 3 seconds, food is presented while the tone is still sounding. |
| B. Simultaneous | II. A tone and food are presented to a dog at the same time |
| C. Backward | III. Food is presented to a dog, and after it is taken away, a tone is sounded. |
| D. Delayed | IV. A tone is played for 5 seconds and then stopped. After a 2-second interval, food is presented to a dog. |
1
A-I, B-II, C-III, D-IV
2
A-IV, B-III, C-II, D-I
3
A-IV, B-II, C-III, D-I
4
A-I, B-III, C-II, D-IV