Consider the following statements.
1. System theory is die result of die behavioural revolution in social science.
2. There is a universally acceptable definition of a system.
3. System theory aims at die unification of science and scientific analysis.
Which of these statements is/are correct?

A. 1 and 3

B. 1 and 2

C. 2 and 3

D. Only 3

Answer: Option D