Totipotency refers to:

The correct answer is Option (3) → Capacity to generate a whole plant from any cell/explant

Totipotency is the ability of a single plant cell or explant (any part of a plant taken out and grown in a test tube) to grow into a whole plant. It is the basis of tissue culture.

(1) Method of producing thousands of plants through tissue culture — Incorrect. This is micro-propagation. It makes use of totipotency but it is the method, not the capacity.

(2) Method of producing genetically identical plants — Incorrect. The plants grown in this way are genetically identical to the original plant and are called somaclones. This describes the result, not the capacity.

(3) Capacity to generate a whole plant from any cell/explant — Correct. This is the meaning of totipotency.

(4) Capacity to generate whole animal from any virus/bacteria — Incorrect. No such term exists. Totipotency is about plant cells.

NCERT Extract:
Biotechnological Applications in Agriculture – …