The pattern of firing of receptor activity in response to red would be

a. large firing from the s receptor, medium firing from the m receptor, and little firing from the l receptor large firing from the s receptor,

b. large firing from the m receptor, and little firing from the l receptor little firing from the s receptor,

c. a moderate firing from the m receptor, and large firing from the l receptor large firing from the s receptor,

d. large firing from the m receptor, and large firing from the l receptor