What is/are the major difference(s) between disc and turbine type stirrer?

Question: What is/are the major difference(s) between disc and turbine type stirrer?
[A].

Blades in disc type are projected out beyond the edge of disc while blades are curved one in turbine type

[B].

Turbine type requires 50 % less air than disc type for the same yield and energy consumption

[C].

Both (a) and (b)

[D].

Number of blades in the stirrer

Answer: Option C

Explanation:

No answer description available for this question.