Garbage in, Garbage out

Paheli gave the following ill effects of the practice of burning dried leaves and other plant parts
(i) Burning degrades the soil.
(ii) Burning produces harmful gases/fumes.
(iii) Precious raw materials to obtain manure at low cost is lost.
(iv) Lot of heat is generated unnecessarily.
The correct reasons of why we should not burn leaves are
(a) i, ii and iv only
(b) i, ii, iii, and iv
(c) ii and iii only
(d) ii, iii, and iv only