What is the minimum speed classification of an AAC Category E aircraft?

The minimum speed classification for an AAC Category E aircraft is correctly identified as 166 knots or more. This classification pertains to the aircraft's approach speed, which is vital for ensuring safe operations, particularly in terms of wake turbulence and spacing between aircraft during landing and takeoff.

Category E aircraft are typically larger and heavier than those in lower categories, and they exhibit significantly higher stall speeds. This consequent increase in speed must be managed during approach and landing to maintain safety margins, especially in environments where different categories of aircraft are operating together.

In considering the other options, 120 knots, 150 knots, and 200 knots do not meet the standard for Category E classification, which is defined specifically by its minimum speed requirement of 166 knots. These numbers reflect general speeds that may apply to smaller categories or specific operational contexts but are not relevant to the strict metric used for Class E aircraft categorization.