Which of the following induces sprouting of potato tubers?

Which of the following is a gaseous plant growth regulator?

Which one is not an ethylene effect?

The gaseous plant growth regulator is used in plants to :

$A$ farmer grows cucumber plants in his field. He wants to increase the number of female flowers in them. Which plant growth regulator can be applied to achieve this?

Describe: $(1)$ volatile endocrine