Which of the following crop requires clear sky during flowering stage?

wheat rice cotton soyabean

cotton

Cotton is a tropical crop grown in kharif season in semi-arid areas of the country. India lost a large proportion of cotton growing area to Pakistan during partition. However, its acreage has increased considerably during the last 50 years. India grows both short staple (Indian) cotton as well as long staple (American) cotton called ‘narma’ in north-western parts of the country. Cotton requires clear sky during flowering stage.