The hyperconjugative stabilities of tert-butyl cation and 2-butene, respectively, are due to
(A) σ→p (empty) and σ→π* electron delocalisations.
(B) σ→σ* and σ→π electron delocalisations.
(C) σ→p (filled) and σ→π electron delocalisations.
(D) p(filled)→σ * and σ→π* electron delocalisations.
