When an aircraft has both outboard and inboard ailerons installed, which of the following statements is true?

a. Inboard ailerons are activated at higher speeds when the outboard ailerons may be deactivated to prevent the twisting of wing surfaces.

b. Outboard ailerons are activated at higher speeds when the inboard ailerons may be deactivated to prevent the twisting of wing surfaces.

c. Inboard and outboard ailerons are activated at all speeds and work in conjunction with each other to mitigate twisting forces.

d. Inboard ailerons are deactivated at higher speeds when spoilers are installed on the aircraft.