The "and" in (C) is a "logical" connective, since the truth of (C) is completely determined by (A) and (B): it would make no sense to affirm (A) and (B) but deny (C).
В качестве основных обычно называют конъюнкцию (formula_1 или &), дизъюнкцию (formula_2), импликацию (formula_3), отрицание (formula_4).