(D) Forest
Forest area in India has shown a marginal increase over the years, while permanent pasture, barren land, and land unsuitable for agriculture have decreased or remained stagnant.
Source: Resources and Development, Land Use Pattern in India
The textbook states that land under permanent pastures has decreased. Barren/waste land and non-agricultural uses have not shown notable increases. Forest cover, though still far below the desired 33%, has registered a marginal increase since 1960-61, making (D) Forest the correct answer. Remember: the question asks which category has seen an increase — elimination of the other options is a useful strategy here.