Answer:
B. 5√6
Explanation:
These are all like terms or like radicals so we can just do the operations. When we say like radicals they have the same root and radicand.
ex.
√ab and √ab
3√3 and 2√3
Notice that both have √3, same root and same radicand so they are like terms.
Now going back to your problem:
4√6 + 2√6 - √6
Just add/subtract the coefficients and copy the radicand since they are like radicands.
4√6 + 2√6 - √6
= 6√6 - √6
= 5√6