Answer:
A. 
Step-by-step explanation:
We are given,
The cost of one book = $2.25
Since, it takes $2.25 to buy 1 book.
The, for $10, we can get
i.e.
= 4.44
Since, number of books cannot be in decimals.
So, the closest integer to 4.44 is 4.
Hence, we can buy 4 books from $10.
Now, according to the options:
A. 
B. 
C. 
D. 
Hence, we see that from the options, A is correct.