Tissue culture is recommended for

1. Production of virus free plants
2. Induction of polyploidy
3. Phytoremediation
4. Gene cloning

the correct option is 1.
Tissue culture is the growth of tissues or cells separate from the organism. This is typically facilitated via use of a liquid, semi-solid, or solid growth medium, such as broth or agar. Tissue culture commonly refers to the culture of animal cells and tissues, with the more specific term plant tissue culture being used for plants.

The production of new plants from a small piece of plant tissue removed from the growing tips of a plant in a suitable growth medium is called tissue culture .