The correct option is C 54
Let’s check all the options one by one.
a) 45 has 4 tens and 5 ones.
b) 540 has 5 hundreds, 4 tens, and 0 ones.
c) 54 has 5 tens and 4 ones.
d) 504 has 5 hundreds, 0 tens, and 4 ones.
So, 54 is the number that is represented by 5 tens and 4 ones.