Which of the following is true for Auxin? 
(i) They help to prevent fruit and leaf drop at early stages but promote the abcission of older mature leaves and fruits.
(ii) Auxins prevent apical dominance thus it is applied to tea plantations and hedge-making.
(iii) NAA (naphthalene acetic acid) and 2, 4-D (2, 4-dichlorophenoxyacetic acid) are synthetic auxins.
(iv) Auxins also induce parthenocarpy, e.g., in tomatoes.
(v) 2, 4-D is used to prepare weed-free lawns by gardeners.
(vi) Auxin also controls xylem differentiation and helps in cell division.