British Carrier Section

I have a little question about the british Carrier Section from the infantry Slot from a british armoured battlegroup. Counts this Section as "Platoon" for the Army size rule? Because the Section generate 3 Support options.

Nope, it´s not a platoon by the book.
But, if you want, you could field two individual sections and the carrier platoon and arrange with your opponent that that´s your compulsory platoon.