Which among the following are the artificial ecosystems?
(i) Estuaries
(ii) Mountain
(iii) Crop field
(iv) Grassland
(v) Coral reefs
(vi) Park
(vii) Mangroves
(viii) Aquarium
(A) (i), (ii) and (v) only
(B) (ii), (iv) and (vi) only
(C) (iii), (vi) and (viii) only
(D) (ii), (vi) and (vii) only