Answer:
d. The income effect must have been bigger than the substitution effect since we observe Emily buying less ice cream.
Step-by-step explanation:
Since in the given situation it is mentioned that the ice cream is increased and she adjust her optimal consumption so that she purchased less ice cream and more chocolate so here the income effect would be high as compared with the subsitution effect as the high price of the ice cream decrease the real income with the actual income left and it would lead to purchase less