单项选择题
A．All senses have their limitations. B．Insects are more sensitive to colours than man. C．Man has not fully utilized all his senses. D．Man is not as good as animals in learning about the environment.
A．from the sense of direct touch B．through the difference in temperature C．through skin contact D．from the even distribution of pressure
A．Man is more colour-conscious than the honey-bee. B．The honey-bee is blind to red. C．The honey-bee can see far more colours than man. D．Man is sensitive to the ultra-violet.