Question

Pollen grains can be stored for several years in liquid nitrogen having a temperature of

• A. $-80C^{\circ }$
• B. $-160C^{\circ }$
• C. $-120C^{\circ }$
• D. $-196C^{\circ }$

Answer 1

The correct option is D $-196C^{\circ }$

Cryopreservation

Cryopreservation is a technique to store and preserve cells, tissues and organs at a low temperature of $-196C^{\circ }$ in liquid nitrogen to maintain their viability for future use.
For example, pollen grains are stored in liquid nitrogen at $-196C^{\circ }$ to preserve them for various future purposes like research and farming.

Final answer
$-196C^{\circ }$