Which of the following statements is true regarding the mechanism of action of Bt toxin in Bt Cotton plants?

Bt toxin remains active throughout the plant's life cycle and affects all insects that come in contact with the plant.

The Bt toxin is initially an inactive protoxin that becomes active in the acidic gut environment of the insect, leading to its death.

The Bt toxin protein, in its inactive form, is converted into an active toxin in the alkaline gut of the insect, causing cell lysis and death.

Bt toxin selectively targets plant cells, causing them to become toxic to all types of insects.