Institutional Theory suggests which of the following?

a. While organisational structures are initially varied, they are gradually homogenised by competition, the state and professions.

b. While organisational structures are initially homogenous, they are gradually varied by competition, the State and professions.

c. The organisational structure is determined by institutional factors such as management style and organisational culture.

d. The organisational structure is determined by the organisation's most powerful stakeholders.