单项选择题
A．all nature has come back to life and becomes active B．it is followed by summer C．all kinds of flowers are in full bloom D．it is warm and pleasant
A．nothing to do with man’s mental abilities B．some effect on the intelligence of most people C．a great effect on everyone’s intelligence D．no effect on women’s intelligence
A．varies from month to month B．remains tile same all the year round C．varies with the seasons D．changes without stopping