Silviculture is the branch of botany which deals with the study of :

Development of forests

The correct answer is Option (3) – Development of forests

Silviculture is the art and science of controlling the establishment, growth, composition, health, and quality of forests and woodlands to meet the diverse needs and values of landowners and society such as wildlife habitat, timber, water resources, restoration, and recreation on a sustainable basis.

Silviculture can be defined as the art and science of controlling the composition, structure, and dynamics of forests.

Although the traditional focus of silviculture was on timber production, modern silviculturalists are expected to respond to society's often conflicting demands about forests.

Sustained yield of timber is still a common goal, but non-timber forest products (NTFPs) such as medicinal plants and wildlife sometime receive as much or more attention from some important forest stakeholders .