Answer:
a. Lucia's current bundle maximizes her utility, and she should keep it unchanged.
Explanation:
The computation is shown below:
As we know that the utility would be maximized when the marginal rate of substitution is equivalent to the price ratio
I.e.
MRS = Price ratio
Here, Price ratio is
= $4.5 ÷ $1.5
= 3
So the 3 would also represent the marginal rate of substitution (MRS)
Therefore the correct option is a.
hence, the rest of the options would be incorrect