In which industry structure is advertising and sales promotion likely to be most important?

Anthropologist E. T. Hall in his book The Silent Language said that:

a. What people do is more important than what they say b. Silence is meaningful c. Conflict is everything d. Beware of underlying messages

Assume X and Y are the only two goods a person consumes. If after a rise in the quantity demanded of Y increases, one could say

a. the income effect dominates the substitution effect for Y. b. the substitution effect dominates the income effect for Y. c. it is impossible to determine whether the substitution or income effect dominates for Y. d. None of the above.