To ensure that a given root definition is rigorous and comprehensive, The Lancaster team proposed several criteria that are summarized in the mnemonic CATWOE in Soft Systems Methodology (SSM).Which of the following alphabet is representing an entirely different meaning to SSM ?

A. C – Customer
B. A – Actor
C. T – Transformation
D. E – ER Model

Explanation: ‘E’ in CATWOE stands for Environmental constraints.