Who among the following psychologists is known as the propagator of the theory concerning trial and error learning?

. . . . . . . . technique has also been used in the treatment of behaviour disorders through behaviour therapy.

Stimulus substitution theory:

Match List-I with List-II and select the correct answer:

List-I (Form of conditioning)	List-II (Explanation)
A. Simultaneous conditioning	1. The onset of conditioning stimulus precedes the on set of unconditioned stimulus, conditioned stimulus ends before the end of the unconditioned stimulus
B. Delayed conditioned	2. The on set of conditioned stimulus and unconditioned stimulus are concurrent
C. Trace	3. On set and end of the conditioned stimulus precedes the on set of unconditioned stimulus with some blank time between the two
D. Backward conditioning	4. Unconditioned stimulus precedes the on set of conditioned stimulus

Consider the following statements:
1. Appetitive classical conditioning is slower
2. Appetitive conditioning requires greater number of acquisition trials
3. Aversive conditioning is established in one, tow or three trials
4. Establishing Aversive conditioning is dependent on the intensity of the aversive unconditioned stumulus
Select the correct sentences from the following options: