Totipotency refers to the capacity of a -

Cell or tissue to produce whole plant in-vitro.

The correct answer is Option (1) → Cell or tissue to produce whole plant in-vitro.

Totipotency can be defined as the capacity of a single cell or explant to generate a whole plant in vitro. This means that under the right conditions, a single cell or a small piece of plant tissue (explant) has the potential to give rise to all the cell types and structures necessary to develop into a complete, mature plant. This property is fundamental in plant tissue culture and regeneration techniques, where scientists can use cells or explants to propagate and produce new plants. The ability of a cell to differentiate into various specialized cell types is a characteristic feature of plant cells, which allows for totipotency.