The correct answer would be the second option. The correct plan for his experiment would be that the temperature, the type of limestone, and the type of acid are controls. The amount of acid and the amount of damage to the limestone are variables. To determine the degree of damage of the acid it would be best that the amount of acid is the manipulated variable while everything else are assumed constant.
It is to deliver appropriately qualified civilian men for the induction into the Armed Forces of the US as authorized by Congress.
Answer: c) Spontaneous recovery
Explanation:
Spontaneous recovery is the mechanism in which conditioned response that was gone or vanished earlier occurs again after some period of time .Instant re-emergence of any memory, phobia, fear, thought that was previously gone is faced after time delay .
According to the question, Mariah is experiencing spontaneous recovery in which is facing water fear again after time delay even when she took swimming course to get rid this fear.
Other options are incorrect because observation learning, extinction and generalization is not determine classical conditioning process.Thus, the correct option is option(c).